KR102524731B1 - Systems and/or methods for providing epdcch in a multiple carrier based and/or quasi-collated network - Google Patents

Abstract

ePDCCH is provided. For example, the WTRU may receive configuration to monitor ePDCCH resources. Based on this configuration, the WTRU may be configured and monitor the ePDCCH resource in a particular subframe. Additionally, the WTRU may derive an aggregation level for the subframe associated with an aggregation level number (NAL). The WTRU may transmit or monitor the ePDCCH using the aggregation level associated with the NAL for the subframe. The WTRU may also receive a reference signal. The WTRU may then determine the type of reference signal received. The WTRU may demodulate the PDSCH or ePDCCH using demodulation timing based on the determined type. The ePDCCH or PDSCH may also be monitored or received by the WTRU implicitly identifying demodulation reference timing based on the location of one or more ePDCCH resources on which to receive the DCI.

Description

System and/or method for providing EPDCCH in multi-carrier-based and/or quasi-combined network

Cross reference to related applications

This application claims the benefit of U.S. Provisional Patent Application Serial No. 61/591,508, filed January 27, 2012; 61/612,834 filed March 19, 2012; 61/688,164 filed May 9, 2012; 61/644,972 filed May 9, 2012; 61/678,612 filed August 1, 2012; 61/706,119 filed September 26, 2012; 61/720,646 filed on October 31, 2012; and 61/753,279, filed on January 16, 2013, the contents of these priority applications are incorporated herein by reference.

Current communication systems (eg, LTE/LTE-Advanced systems) may provide multiple antennas, multiple component carriers, and/or quasi-collated antenna ports to support transmission. These multiple antennas, multiple component carriers, and/or pseudo-combined antenna ports may serve a variety of purposes, including peak system throughput enhancement, extended cell coverage, higher Doppler support, and the like. Unfortunately, such communication systems provide an ePDCCH design focused on a single component carrier (rather than, eg, multiple component carriers and/or multiple antennas) and/or are not well suited to support quasi-combined antenna ports, so The performance of multi-carrier systems may be limited and/or may not be properly designed to avoid errors in frames and/or subframes (eg, specific subframes), requiring more stringent PDSCH and/or CSI reporting processing times. and does not provide appropriate PUCCH resource allocation, does not provide PDCCH indications during configuration and/or reference symbols that can be pseudo-combined with antenna ports, and does not provide sufficient time for use by ePDCCH and/or decoding thereof. can

Systems, methods, and means for providing an ePDCCH in a multi-carrier communication system are disclosed. For example, a UE or WTRU may accept a configuration to monitor ePDCCH resources. Based on such a configuration, a UE or WTRU may be configured to monitor ePDCCH resources in a particular subframe. The WTRU may then monitor ePDCCH resources in subframes. In an exemplary embodiment, the subframe may not be a special subframe, the configuration may be accepted through higher layer signaling, the configuration monitors in ePDCCH resources when the PRB set includes the eCCE set including the eREG, and other PDCCH resources are also monitored in the subframe, and one or more PRB sets for demodulating ePDCCH resources may be included.

Systems, methods and means for providing ePDCCH based on aggregation level are also disclosed. For example, a UE or WTRU may derive an aggregation level for a subframe (eg, an eCCE aggregation level). The UE or WTRU may derive such an aggregation level based on an aggregation level number (N _AL ) for the subframe (in one embodiment, N _AL is a positive integer). The UE or WTRU may transmit or monitor the ePDCCH according to or using the aggregation level associated with the N _AL of the subframe. For example, if the search space is {1,2,4,8} and N _AL is 2, the UE or WTRU may monitor according to {2,4,8,16}.

Systems, methods and means for receiving or monitoring ePDCCH or PDSCH are also disclosed herein. For example, a UE or WTRU may receive a reference signal. The UE or WTRU may then determine the type of reference signal received. A UE or WTRU may perform demodulation of the PDSCH or ePDCCH using demodulation timing based on the type. For example, when the reference signal is a channel state information reference signal (CSI-RS), PDSCH demodulation may be performed using demodulation reference timing based on Fast Fourier Transform (TFT) timing and channel estimation coefficients related to the CSI-RS. there is. In a further embodiment, the ePDCCH or PDSCH may be monitored by implicitly identifying a demodulation reference signal based on the location of one or more ePDCCH resources on which the UE or WTRU receives downlink control information (DCI).

A more detailed understanding can be obtained from the following description given by way of example in conjunction with the accompanying drawings.
1A is an illustration of an exemplary communications system in which one or more embodiments of the present invention may be implemented.
FIG. 1B is a schematic diagram of an exemplary wireless transmit/receive unit (WTRU) that may be used in the communications system shown in FIG. 1A.
1C is a schematic diagram of an exemplary radio access network and an exemplary core network that may be used in the communication system shown in FIG. 1A.
1D is a schematic diagram of another example radio access network and an example core network that may be used in the communication system shown in FIG. 1A.
1E is a schematic diagram of another example radio access network and an example core network that may be used in the communication system shown in FIG. 1A.
2 is a diagram illustrating an exemplary embodiment of a WTRU or UE specific precoded DM-RS.
3 is a diagram illustrating an exemplary embodiment of a non-precoded cell specific RS.
4 is a diagram illustrating an example embodiment of a WTRU or UE specific DM-RS for a normal CP (eg port 5);
5A-5C are diagrams of an exemplary embodiment of a CRS structure based on the number of antenna ports.
6 is a diagram showing an exemplary embodiment of a DM-RS pattern supporting, for example, eight layers.
7 is a diagram illustrating an example embodiment of a CSI-RS pattern that can be reused based on the number of ports.
8 is a diagram of an exemplary embodiment of a positioning architecture.
9 is a diagram illustrating an exemplary embodiment of REG definition in a downlink control channel region with 2Tx CRS.
10 is a diagram illustrating an exemplary embodiment of REG definition in a downlink control channel region with 4Tx CRS.
11 is a diagram illustrating an exemplary embodiment of PCFICH REG allocation based on PCI.
12 is a diagram illustrating an exemplary embodiment of PCFICH and PHICH REG allocation based on PCI.
13 is a diagram illustrating an exemplary embodiment of an ePDCCH multiplexed with a PDSCH (eg, FDM multiplexing).
14 is a diagram showing an exemplary embodiment of mapping of PUCCH to physical resource blocks.
15 is a diagram illustrating an exemplary embodiment of a collision between a DM-RS and a PRS.
16 is a diagram illustrating an exemplary embodiment of ePDCCH resource allocation in a subframe.
17 is a diagram illustrating an exemplary embodiment of carrier aggregation with different TDD UL-DL configurations.
18 is a diagram illustrating an exemplary embodiment of CCE aggregation over multiple carriers in distributed resource allocation.
19 is a diagram illustrating an example embodiment of a PRB-pair used for ePDCCH transmission based on multiple antenna ports (eg, ports 7-10 and 7-8, respectively).
20 is a diagram illustrating an exemplary embodiment of eCCE-eREG mapping in an ePDCCH based on localized and/or distributed assignments.
21 is a diagram illustrating an exemplary embodiment of eCCE-eREG mapping with contiguous allocation.
22 is a diagram illustrating an exemplary embodiment of a block interleaver.
23 is a diagram illustrating an exemplary embodiment of hybrid allocation using a block interleaver.
24 is an illustration of an exemplary embodiment of the coexistence of localized and/or distributed eCCEs.
25 is a diagram illustrating an exemplary embodiment of antenna port mapping for eREG and eCCE.
26 is a diagram illustrating an exemplary embodiment of a common search space definition in a legacy PDCCH region of a PCell.

Details of exemplary embodiments will now be described with reference to the drawings. Although the embodiments herein are described with respect to exemplary embodiments, the embodiments are not limited to the embodiments described herein and other embodiments may be used, or modifications and additions may be made without departing from the scope of the present invention. It is possible for the embodiments described herein to perform the same or similar functions as those of the present invention. Also, the figures merely show an exemplary call flow. It should be understood that other embodiments may be used. The order of flow can be different. Also, a flow may be omitted if not implemented, and additional flows may be added.

A system and/or method for providing an efficient downlink control channel design (eg, an enhanced downlink control channel) in a multi-carrier based wireless network (eg, the network shown in FIGS. 1A-1E ). For example, such systems and/or methods may provide and/or use localized and/or distributed resource allocation in a multi-carrier system, including distributed resource allocation across multiple component carriers. In addition, PDSCH and/or CSI feedback processing time mitigation including flexible PDSCH processing time adaptation based on multi-component carrier reception with ePDCCH and/or flexible CSI reporting time adaptation based on reporting bandwidth, number of component carriers, etc. / or can be provided and / or used in a method. In an embodiment, such systems and/or methods also include new assignment of ePDCCH physical and/or logical addresses (eg, CCE index) and/or cross-carrier scheduling to the relationship of the uplink control channel and/or ePDCCH and /or may provide and/or use legacy uplink control signaling relationships. TDD-specific embodiments for such systems and/or methods may also be provided and/or used, including ePDCCH usage in specific subframes and/or TDD inter-bands. According to an exemplary embodiment, a PDCCH fallback transmission mode is provided in the system and/or method in case of UE or WTRU behavior of PDCCH reception in an ambiguity period by RRC-configured PDCCH configuration between legacy PDCCH and ePDCCH. may be provided and/or used for

Additionally, such systems and/or methods may provide and/or use flexible eREG and/or eCCE definitions, including, for example, full FDM-based eREG definitions. Such systems and/or methods include eCCE-eREG mapping based on ePDCCH transmission mode, interleaver design based on variable eREG and/or eCCE definition, and adaptive eREG-eCCE mapping (e.g., according to reference signal overhead in subframes). variable number of eREGs per eCCE); and the like. In an embodiment, antenna port associations for eREGs and/or eCCEs, including location and/or aggregation level based antenna port mapping and/or PRG size definition for PRB bundling, are provided in such systems and/or methods and/or or may be used. For example, ePDCCH search including PUCCH allocation based on a common search space and/or WTRU or UE specific search space, TBS constraints according to TA and/or CSI feedback requests, and/or ePDCCH with multiple downlink component carriers. A spatial design may also be provided and/or used with such systems and/or methods.

According to one embodiment, such a system and/or method is a combination of RE location based mapping and/or WTRU or UE specific configuration and/or antenna port mapping rules based on a common search space and WTRU or UE specific in distributed transmission. may provide and/or use antenna port associations with WTRU or UE specific configurations including type search spaces. In an embodiment, collision handling between legacy signals other than PDSCH and ePDCCH resources including rate matching and/or puncturing rules may be provided and/or used for the system and/or method. Additionally, adaptive eREG-eCCE mapping, mapping rules based on subframe characteristics, and the like may be provided and/or used. In further embodiments, TBS limitation of TDD mode according to HARQ-ACK timing may be provided and/or used.

Such systems and/or methods may also provide and/or use ePDCCH resources. For example, a plurality of ePDCCH resource sets with a variable resource size per set may depend on a downlink control information (DCI) format depending on an ePDCCH candidate, an ePDCCH resource set depending on a hash function, and/or the number of ePDCCH resource sets. It may be provided and/or used according to the system bandwidth including the ePDCCH indication for

PUCCH (A/N) resource allocation of ePDCCH with MU-MIMO support may also be provided and/or used (eg, in the system and/or method).

In an embodiment, such systems and/or methods may also provide PRS conflict handling techniques including broadcasting of PRS configuration information and/or provision of WTRU or UE behavior when ePDCCH resources collide with PRS.

Multiple sets of ePDCCH resources in a multi-carrier system may also be provided and/or defined by such systems and/or methods. For example, a DM-RS sequence may be defined. In such an embodiment, a DM-RS sequence generator (XID) may be provided, used and/or specified per ePDCCH set or for each ePDCCH set. Additionally, when a WTRU or UE receives a PDSCH associated with an ePDCCH, the same XID received from the ePDCCH may be used for PDSCH demodulation. In further embodiments, PUCCH resource allocation by multiple sets of ePDCCH resources may be provided and/or used, and/or search space definitions and/or aggregation levels of localized transmissions including hash function definitions specific to ePDCCH transmissions. eCCE indexing specific to an ePDCCH transmission may be provided and/or used, such as different eCCE indexing according to aggregation or based on aggregation level. eREG-eCCE mapping may also be provided and/or used. For example, cell specific eREG to eCCE mapping based on localized and distributed transmissions may be provided and/or used. In an embodiment, for example, a subset of transmission modes supported by ePDCCH and/or supportable ePDCCH types that may differ (eg, depending on transmission scheme) (eg, localized and distributed) ), supported transmission modes associated with the ePDCCH may also be provided and/or specified.

Additionally, such systems and/or methods may provide ePDCCH WTRU or UE specific search spaces (eg, related equations) and hash functions. For example, search space equations of localized and/or distributed ePDCCHs and/or hash functions with a plurality of ePDCCH sets may be provided and/or used.

Such systems and/or methods may include eREG/eCCE definitions for common search spaces, start symbols (eg, interrelated ones), resource definitions/configuration, and/or redundant resources between the UE-specific search space and the common search space. An ePDCCH common search space including support may also be provided.

A system and method for providing demodulation reference timing indications are disclosed. For example, single demodulation reference timing support and multiple demodulation reference timing support, such as resource specific demodulation reference timing and indication of demodulation reference timing (eg, demodulation reference timing indication), may be provided as described herein.

1A is a diagram of an exemplary communications system 100 in which one or more embodiments of the present invention may be implemented. The communication system 100 may be a multi-access system that provides content such as voice, data, video, message, and broadcasting to a plurality of wireless users. The communication system 100 allows multiple wireless users to access the content by sharing system resources including wireless bandwidth. For example, communication system 100 may use one such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), and the like. The above channel access methods can be used.

As shown in FIG. 1A , communication system 100 includes wireless transmit/receive units (WTRUs) 102a, 102b, 102c, and/or 102d (collectively or collectively referred to as WTRUs 102 ). (also referred to as), radio access network (RAN) (103/104/105), core network (106/107/109), public switched telephone network (PSTN) (108), Internet ( 110) and other networks 112, it will be appreciated that embodiments of the present invention may include any number of WTRUs, base stations, networks and/or network elements. Each WTRU 102a, 102b, 102c, 102d may be any type of device configured to operate and/or communicate in a wireless environment. For example, the WTRUs 102a, 102b, 102c, 102d may be configured to transmit and/or receive radio signals, and may be configured to transmit and/or receive radio signals, user equipment (UE), mobile stations, fixed or mobile subscriber units, pagers, cellular telephones, personal information It may include personal digital assistants (PDAs), smartphones, laptops, netbooks, personal computers, wireless sensors, consumer electronics, and the like.

The communication system 100 may also include a base station 114a and a base station 114b. Each base station 114a, 114b wirelessly interfaces with at least one WTRU 102a, 102b, 102c, 102d to access the core network 106/107/109, the Internet 110, and/or network 112. It may be any type of device configured to access one or more communication networks. For example, base stations 114a and 114b may include base transceiver stations (BTS), Node-Bs, eNode Bs, Home Node Bs, Home eNode Bs, site controllers, access points (APs), It may be a wireless router or the like. Although base stations 114a and 114b are each shown as a single element, it will be appreciated that base stations 114a and 114b may include any number of interconnected base stations and/or network elements.

Base station 114a may be part of a RAN 103/104/105, which may include a base station controller (BSC), a radio network controller (RNC), and a relay node. It may also include other base stations and/or network elements (not shown) such as the like. Base station 114a and/or base station 114b may be configured to transmit and/or receive wireless signals within a specific geographic area, also referred to as a cell (not shown). A cell may be subdivided into a plurality of cell sectors. For example, a cell associated with base station 114a may be divided into three sectors. Thus, in one embodiment, base station 114a may include three transceivers, one for each sector of the cell. In another embodiment, base station 114a may use multiple-input multiple-output (MIMO) technology, and thus may use multiple transceivers for each sector of the cell.

The base station 114a, 114b may be a radio interface (115/116/116/116/115/116) which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible, etc.) 117) to communicate with one or more WTRUs 102a, 102b, 102c, 102d. The air interface 115/116/117 may be established using any suitable radio access technology (RAT).

More specifically, as noted above, communication system 100 may be a multiple access system and may utilize one or more channel access schemes such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, base station 114a in RAN 103/104/105 and WTRUs 102a, 102b, 102c establish air interfaces 115/116/117 using Wideband CDMA (WCDMA) Universal Mobile Communications system (UMTS) may implement a radio technology such as Terrestrial Radio Access (UTRA). WCDMA may include communication protocols such as High Speed Packet Access (HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink Packet Access (HSDPA) and/or High-Speed Uplink Packet Access (HSUPA).

In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c communicate over the air interface 115/116/117 using Long Term Evolution (LTE) and/or LTE-Advanced (LTE-A). It is possible to implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA) that establishes

In another embodiment, the base station 114a and the WTRUs 102a, 102b, 102c conform to IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 IX, CDMA2000 EV-DO, Interim Standard 2000 (IS -2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), and GSM EDGE (GERAN). can be implemented

Base station 114b of FIG. 1A may be, for example, a wireless router, home node B, home eNode B, or access point, and any suitable device that enables wireless connectivity in a local area, such as a business, home, automobile, campus, and the like. RAT can be used. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In another embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In another embodiment, the base station 114b and the WTRUs 102c, 102d may establish a picocell or femtocell using a cellular based RAT (eg, WCDMA, CDMA2000, GSM, LTE, LTE-A, etc.) can As shown in FIG. 1A , base station 114b may be directly connected to Internet 110 . Therefore, base station 114b does not need to access Internet 110 via core network 106/107/109.

The RAN 103/104/105 communicates with the core network 106/107/109, which provides voice, data, and application information to one or more WTRUs 102a, 102b, 102c, and 102d. and/or any type of network configured to provide voice over internet protocol (VoIP) services. For example, the core network 106/107/109 may provide call control, billing services, mobile location-based services, prepaid calling, Internet access, video distribution, etc., and/or user authentication, etc. It can perform advanced security functions. Although not shown in FIG. 1A, the RAN 103/104/105 and/or the core network 106/107/109 communicate directly with other RANs using the same RAT as the RAN 103/104/105 or a different RAT. or indirect communication. Besides being connected to the RAN 103/104/105 using e.g. E-UTRA radio technology, the core network 106/107/109 also communicates with other RANs (not shown) using GSM radio technology. can do.

The core network 106/107/109 may also act as a gateway for WTRUs 102a, 102b, 102c, 102d to connect to the PSTN 108, the Internet 110, and/or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). Internet 110 is a network of interconnected computers and devices that utilize common communication protocols such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and Internet Protocol (IP) in the TCP/IP Internet Protocol Suite. may include a global system of Networks 112 may include wired or wireless communications networks owned and/or operated by other service providers. For example, network 112 may include other core networks connected to one or more RANs that use the same RAT as RAN 103/104/105 or different RATs.

Some or all of the WTRUs 102a, 102b, 102c, 102d of the communication system 100 may have multi-mode capabilities. That is, the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links. For example, the WTRU 102c shown in FIG. 1A may be configured to communicate with a base station 114a that may utilize a cellular-based radio technology and a base station 114b that may utilize an IEEE 802 radio technology.

1B is a system diagram of an exemplary WTRU 102 . As shown in FIG. 1B, the WTRU 102 includes a processor 118, a transceiver 120, a transmit/receive element 122, a speaker/microphone 124, a keypad 126, a display/touchpad 128, a It may include a removable memory 130 , a removable memory 132 , a power supply 134 , a global positioning system (GPS) chipset 136 and other peripherals 138 . It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment. Further, embodiments may include base stations 114a, 114b, and/or base stations 114a, 114b, by way of non-limiting examples, among other things, a base station transceiver (BTS), a Node-B, a site controller, an access point (AP) ), Home Node-B, Evolved Home Node-B (eNodeB), Home eNode-B (HeNB), Home eNode-B Gateway, and nodes that may represent proxy nodes are shown in FIG. 1B and here It is expected to include some or all of the elements described in

The processor 118 may include a general purpose processor, a special purpose processor, a traditional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), It may be a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), state machine, or the like. Processor 118 may perform signal encoding, data processing, power control, input/output processing, and/or any other function that allows WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to a transceiver 120, and the transceiver 120 may be coupled to a transmit/receive element 122. Although processor 118 and transceiver 120 are shown as separate components in FIG. 1B, it will be appreciated that processor 118 and transceiver 120 may be integrated together into an electronic package or chip.

The transmit/receive element 122 may be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) via the air interface 115/116/117. For example, in one embodiment, the transmit/receive element 122 may be an antenna configured to transmit and/or receive RF signals. In other embodiments, the transmit/receive element 122 may be an emitter/detector configured to transmit and/or receive IR, UV or visible light signals, for example. In another embodiment, the transmit/receive element 122 may be configured to transmit and receive both RF and optical signals. It will be appreciated that the transmit/receive element 122 may be configured to transmit and/or receive any combination of radio signals.

Further, although the transmit/receive element 122 is shown as a single element in FIG. 1B, the WTRU 102 may include any number of transmit/receive elements 122. More specifically, the WTRU 102 may utilize MIMO technology. Thus, in one embodiment, the WTRU 102 includes two or more transmit/receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 115/116/117. can do.

The transceiver 120 may be configured to modulate signals to be transmitted by the transceiver element 122 and demodulate signals received by the transceiver element 122 . As noted above, the WTRU 102 may have multi-mode capabilities. Accordingly, the transceiver 120 may include multiple transceivers that allow the WTRU 102 to communicate via multiple RATs, such as UTRA and IEEE 802.11, for example.

The processor 118 of the WTRU 102 includes a speaker/microphone 124, keypad 126, and/or display/touchpad 128 (e.g., a liquid crystal display (LCD) display or an organic light emitting diode (OLED) display). ) display device) to receive user input data from them. Processor 118 may also output user data to speaker/microphone 124 , keypad 126 , and/or display/touchpad 128 . Additionally, processor 118 may access information from, and store data in, any type of suitable memory, such as non-removable memory 130 and/or removable memory 132. Non-removable memory 130 may include random access memory (RAM), read only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In another embodiment, processor 118 may access information from and store data in memory that is not physically located in WTRU 102, such as a server or home computer (not shown).

Processor 118 may be configured to receive power from power source 134 and distribute and/or control power to various components of WTRU 102 . Power supply 134 may be any suitable device that supplies power to WTRU 102 . For example, power source 134 may include one or more dry cell batteries (eg, nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.) , solar cells, fuel cells, and the like.

Processor 118 may also be coupled to a GPS chipset 136 configured to provide location information (eg, longitude and latitude) regarding the current location of WTRU 102 . In addition to or in lieu of information from GPS chipset 136, WTRU 102 receives location information from base stations (e.g., base stations 114a, 114b) over air interface 115/116/117. and/or determine its location based on the timing at which signals are received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable location-determination method while remaining consistent with an embodiment.

Processor 118 may also be coupled to other peripherals 138 including one or more software and/or hardware modules that provide additional features, functionality, and/or wired or wireless connectivity. For example, peripherals 138 may include accelerometers, e-compasses, satellite transceivers, digital cameras (for photography or video), universal serial bus (USB) ports, vibration devices, television transceivers, hands-free headsets, Bluetooth® modules, may include a frequency modulated (FM) radio device, digital music player, media player, video game player module, Internet browser, and the like.

1C is a system diagram of the RAN 103 and the core network 106 according to one embodiment. As noted above, the RAN 103 may communicate with the WTRUs 102a, 102b, 102c over the air interface 115 using UTRA radio technology. RAN 103 may also communicate with core network 106 . As shown in FIG. 1C , RAN 103 includes Node-Bs 140a, 140b, and 140c, which communicate via air interface 115 with WTRUs 102a, 102b, 102c) may each include one or more transceivers in communication. Node-Bs 140a, 140b, and 140c may each be associated with a specific cell (not shown) within the RAN 103. RAN 103 may also include RNCs 142a and 142b. It will be appreciated that the RAN 103 may include any number of Node-Bs and RNCs while remaining consistent with an embodiment.

As shown in FIG. 1C, Node-Bs 140a and 140b may communicate with RNC 142a. Node-B 140c may also communicate with RNC 142b. Node-Bs 140a, 140b, 140c may communicate with respective RNCs 142a, 142b via an Iub interface. RNCs 142a and 142b may communicate with each other via an Iur interface. Each RNC 142a, 142b may be configured to control each Node-B 140a, 140b, 140c to which it is connected. Each RNC 142a, 142b may also be configured to perform or support other functions such as outer loop power control, load control, admission control, packet scheduling, handover control, macrodiversity, security functions, data encryption, etc. .

The core network 106 shown in FIG. 1C includes a media gateway (MGW) 144, a mobile switching center (MSC) 146, a serving GPRS support node (SGSN) 148 and/or a gateway GPRS support node (GGSN). (150) may be included. Although each of the foregoing elements are shown as part of the core network 106 , it will be appreciated that any of these elements may be owned or operated by an entity other than the core network operator.

RNC 142a in RAN 103 may be connected to MSC 146 in core network 106 via an IuCS interface. MSC 146 may be connected to MGW 144 . The MSC 146 and MGW 144 provide the WTRUs 102a, 102b, and 102c with access to a circuit-switched network, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, and 102c and traditional landline communication devices. make it possible

RNC 142a in RAN 103 may also be connected to SGSN 148 in core network 106 via an IuPS interface. SGSN 148 may be connected to GGSN 150 . The SGSN 148 and GGSN 150 provide the WTRUs 102a, 102b, and 102c with access to a packet-switched network, such as the Internet 110, to facilitate communication between the WTRUs 102a, 102b, and 102c and IP-enabled devices. makes it possible

As noted above, core network 106 may also be connected to network 112, including other wired or wireless networks owned and/or operated by other service providers.

1D is a system diagram of the RAN 104 and the core network 107 according to one embodiment. As noted above, the RAN 104 may communicate with the WTRUs 102a, 102b, 102c over the air interface 116 using E-UTRA radio technology. RAN 104 may also communicate with core network 107 .

Although the RAN 104 includes eNode-Bs 160a, 160b, and 160c, it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 160a, 160b, 160c may each include one or more transceivers that communicate with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, eNode-B 160a, for example, may transmit radio signals to and receive radio signals from WTRU 102a using multiple antennas.

Each eNode-B 160a, 160b, 160c may be associated with a specific cell (not shown), and handle radio resource management decisions, handover decisions, scheduling of users in uplink and/or downlink, etc. can be configured to As shown in FIG. 1D, eNode-Bs 160a, 160b, and 160c may communicate with each other through an X2 interface.

The core network 107 shown in FIG. 1D may include a mobility management gateway (MME) 162 , a serving gateway 164 and a packet data network (PDN) gateway 166 . Although each of the foregoing elements are shown as part of the core network 107 , it will be appreciated that any of these elements may be owned and/or operated by entities other than the core network operator.

MME 162 may be connected to each eNode-B 160a, 160b, 160c in RAN 104 via an S1 interface and may function as a control node. For example, MME 162 authenticates users of WTRUs 102a, 102b, 102c, activates/deactivates bearers, selects particular serving gateways during initial attachment of WTRUs 102a, 102b, 102c, etc. can perform its duties. MME 162 may also provide control plane functions for switching between RAN 104 and other RANs (not shown) using other radio technologies such as GSM or WCDMA.

Serving Gateway 164 may be connected via an S1 interface to each eNode-B 160a, 160b, 160c in RAN 104. The serving gateway 164 may generally route and forward user data packets to/from the WTRUs 102a, 102b, 102c. The Serving Gateway 164 is also responsible for anchoring the user plane during handover between eNode-Bs, triggering paging when downlink data is available to the WTRUs 102a, 102b, 102c. and other functions such as managing and storing the context of the WTRUs 102a, 102b, 102c.

Serving gateway 164 may also be connected to PDN gateway 166, which provides packet communication, such as Internet 110, to facilitate communication between WTRUs 102a, 102b, 102c and IP-enabled devices. Access to a switched network may be provided to the WTRUs 102a, 102b, 102c.

The core network 107 enables communication with other networks. For example, the core network 107 provides access to a circuit-switched network, such as the PSTN 108, to allow communications between the WTRUs 102a, 102b, and 102c and traditional land-line communication devices. , 102b, 102c). For example, the core network 107 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that functions as an interface between the core network 107 and the PSTN 108. can Core network 107 may also provide WTRUs 102a, 102b, 102c access to networks 112, including other wired or wireless networks owned and/or operated by other service providers.

1E is a system diagram of the RAN 105 and core network 109 according to one embodiment. The RAN 105 may be an access service network (ASN) that communicates with the WTRUs 102a, 102b, 102c over an air interface 117 using IEEE 802.16 radio technology. As described in more detail below, the communication link between the RAN 105 and the core network 109, the other functional entities of the WTRUs 102a, 102b, 102c may be defined as a reference point.

As shown in FIG. 1E , although RAN 105 includes base stations 180a, 180b, and 180c and an ASN gateway 182, RAN 105 can accommodate any number of base stations and ASNs while remaining consistent with an embodiment. It will be appreciated that it may include a gateway. Base stations 180a, 180b, 180c may each be associated with a specific cell (not shown) within RAN 105 and may each have one or more transceivers in communication with WTRUs 102a, 102b, 102c over air interface 117. each can be included. In one embodiment, base stations 180a, 180b, and 180c may implement MIMO technology. Thus, for example, base station 180a may transmit radio signals to and receive radio signals from WTRU 102a using multiple antennas. Base stations 180a, 180b, 180c may also provide mobility management functions such as handoff triggering, tunnel establishment, radio resource management, traffic classification, quality of service (QoS) policy enforcement, and the like. ASN gateway 182 may function as a traffic aggregation point and may perform duties such as paging, caching of subscriber profiles, and routing to core network 109 .

The air interface 117 between the WTRUs 102a, 102b, 102c and the RAN 105 may be defined as an R1 reference point implementing the IEEE 802.16 specification. Each WTRU 102a, 102b, 102c may also establish a logical interface (not shown) with the core network 109. A logical interface between the WTRUs 102a, 102b, 102c and the core network 109 may be defined as an R2 reference point, which is used for authentication, authorization, IP host configuration management, and/or mobility management. can be used

The communication link between each of the base stations 180a, 180b, and 180c may be defined as an R8 reference point that includes protocols that enable WTRU handover and data transfer between base stations. The communication link between base stations 180a, 180b, 180c and ASN gateway 182 may be defined as an R6 reference point. The R6 reference point may include protocols that enable mobility management based on mobility events associated with each WTRU 102a, 102b, 102c.

As shown in FIG. 1E , RNA 105 may be connected to core network 109 . The communication link between the RAN 105 and the core network 109 may be defined as an R3 reference point, including protocols enabling data transfer and mobility management capabilities, for example. The core network 109 may include a mobile IP home agent (MIP-HA) 184 , an authentication, authorization, and accounting (AAA) server 186 , and a gateway 188 . Although each of the foregoing elements are shown as part of the core network 109 , it will be appreciated that any of these elements may be owned and/or operated by entities other than the core network operator.

The MIP-HA may be tasked with managing IP addresses and may allow the WTRUs 102a, 102b, 102c to roam between different ASNs and/or different core networks. MIP-HA 184 provides WTRUs 102a, 102b, 102c with access to a packet-switched network, such as Internet 110, to enable communication between WTRUs 102a, 102b, 102c and IP-enabled devices. do. AAA server 186 may be responsible for user authentication and user service support. Gateway 188 enables interworking with other networks. For example, gateway 188 provides WTRUs 102a, 102b, 102c with access to a circuit-switched network, such as PSTN 108, to enable communication between WTRUs 102a, 102b, 102c and traditional landline communication devices. let it Gateway 188 may also provide WTRUs 102a, 102b, 102c access to networks 112, including other wired or wireless networks owned and/or operated by other service providers.

Although not shown in FIG. 1E , it will be appreciated that the RAN 105 can be connected to other ASNs and the core network 109 can be connected to other core networks. The communication link between the RAN 105 and other ASNs may be defined as an R4 reference point, and the R4 reference point may include protocols that coordinate the mobility of WTRUs 102a, 102b, 102c between the RAN 105 and other ASNs. . The communication link between the core network 109 and other core networks may be defined as an R5 reference point, and the R5 reference point may include a protocol that enables interworking between the home core network and the visited core network.

According to an exemplary embodiment, cooperative and/or multi-antenna transmission is provided in a communication system (eg, LTE/LTE-Advanced system) such as communication system 100 described above with respect to FIGS. 1A-1E. It can be. In embodiments, such coordinated transmissions provide that PDSCH transmissions for a WTRU or UE (eg, an LTE-A WTRU or UE) can be dynamically changed between transmission points without a cell selection/reselection procedure and/or or may be used. Downlink control channel transmissions of a WTRU or UE specific RS based type may also be provided and/or used, for example to enhance PDCCH performance.

Additionally, such multi-antenna transmissions may be provided and/or used for a variety of purposes, including peak system throughput enhancement, extended cell coverage, and high Doppler support. For example, single user multiple input multiple output (SU-MIMO) may be used in such communication systems to increase peak and/or average user equipment (UE) or WTRU throughput. Additionally, multi-user MIMO can be used in such communication systems to increase peak and/or average system throughput by taking advantage of multi-user diversity gains. Table 1 shows exemplary MIMO capabilities that can be used in a wireless communication system to improve throughput, diversity gain, and the like.

Example MIMO capabilities of a communication system (eg, LTE/LTE-Advanced) Basic downlink MIMO technology 3GPP E-UTRA LTE LTE-Advanced release 8 release 9 release 10 DL SU-MIMO up to 4 streams up to 4 streams up to 8 streams MU-MIMO up to 2 users
(single precoding) up to 4 users
(non-single precoding) up to 4 users
(non-single precoding) UL SU-MIMO 1 stream 1 stream up to 4 streams MU-MIMO up to 8 users up to 8 users up to 8 users

To support MIMO capability (eg, depending on or based on the WTRU or UE channel environment), for example, up to 9 transmission modes have been used. These transmission modes may include a transmission diversity mode, an open loop spatial multiplexing mode, a closed loop spatial multiplexing mode, and the like. Additionally, MIMO link adaptation may be used and/or provided. In an embodiment, a WTRU or UE may report channel state information (CSI) of multiple transmit antenna ports to enable or facilitate such MIMO link adaptation. For example, reference signals may be provided along with CSI and / or may be used. In one embodiment, the reference signal is provided as a WTRU or UE-specific reference signal (WTRU or UE-RS) and/or cell-specific reference signal (CRS), or may be classified as a WTRU or UE-RS and/or CRS. According to one embodiment, a WTRU or UE-RS may be used for a particular WTRU or UE such that RSs may be transmitted on resources allocated to the WTRU or UE. Additionally, in one embodiment, the CRS may be a cell-specific reference signal that each UE in a cell may share so that the RS may be transmitted in a wideband manner.

Depending on or based on the purpose, the reference signal (RS) can be distinguished, for example, into a demodulation reference signal (DM-RS) and/or a channel state information reference signal (CSI-RS). DM-RS may be used for a special WTRU or UE, and the RS may be precoded to utilize beamforming gains. In an embodiment, the WTRU or UE specific DM-RS may not be shared with other UEs in the cell. Thus, the DM-RS may be transmitted on allocated time and/or frequency resources for a WTRU or UE. Additionally, DM-RS may be limited to use by demodulation.

2 illustrates an exemplary embodiment providing WTRU or UE specific precoded DM-RS. As shown in FIG. 2, if precoded DM-RS is used, the RS can be precoded using the precoding used for data symbols, and the number of RS sequences corresponding to the number of layers (K) can be sent In one embodiment, K may be equal to or less than the number of physical antenna ports (N _T ). Additionally, in FIG. 2 K streams may be allocated for a WTRU or UE and shared with multiple UEs. If a plurality of UEs share K streams, the co-scheduled UEs can simultaneously share the same time/frequency resources.

As mentioned above, a cell specific reference signal (CRS) may be provided and/or used. According to an exemplary embodiment, a CRS may be defined for a UE within a cell and used for demodulation and/or measurement. Additionally, in an exemplary embodiment, the CRS may be shared by UEs. In such an embodiment, a non-precoded RS may be used and/or used, for example, to maintain uniform cell coverage (eg, since the CRS is shared by UEs). Precoded RSs may have different cell coverages depending on the direction and/or due to beamforming effects. 3 shows an exemplary embodiment of a MIMO transmitter that may be used for non-precoded CRS transmission as described herein.

Additionally, in an exemplary embodiment, antenna virtualization may be provided and/or used. For example, if the number of physical antenna ports differs from the number of logical antenna ports, antenna virtualization may be used (eg, with CRS and/or non-precoded CRS transmissions shown in FIG. 3). RS sequences may also be transmitted for antenna ports regardless of the number of streams.

According to exemplary embodiments, other structures may be provided and/or used for DM-RS and/or CRS. 4 shows an exemplary embodiment of a DM-RS (eg, antenna port-5) that may be used (eg, in an LTE system) to support non-codebook based transmission. In one embodiment, the structure shown in Figure 4 can be used, for example, in an eNB, where antenna port-5 can be restricted to supporting layer 1 transmission. Additionally, antenna port-5 shown in FIG. 4 may be transmitted by CRS, so (eg overall) RS overhead may increase.

5 shows an exemplary embodiment of a CRS structure according to the number of antenna ports or based on the number of antenna ports. The CRS patterns of each antenna port (eg, the pattern shown in FIG. 5) may be orthogonal to each other in the time and/or frequency domain. As shown in FIG. 5, R0 and R1 indicate the CRS for antenna port 0 and antenna port 1, respectively. In an embodiment, to avoid interference between CRS antenna ports, data REs located in REs from which CRS antenna ports are transmitted may be muted.

According to an exemplary embodiment, a predefined sequence (eg, pseudo random (PN), m-sequence, etc.) is multiplied with downlink RS to minimize inter-cell interference and/or improve channel estimation accuracy associated with CRS. can do. The PN sequence may be applied at the OFDM symbol level in a subframe, and the sequence may be defined according to a cell ID, a subframe number, a location of an OFDM symbol, and the like. For example, the number of CRS antenna ports can be 2 in an OFDM symbol containing one CRS per PRB, and the number of PRBs in a communication system such as an LTE system can vary from 6 to 110. In such an embodiment, the total number of CRSs for antenna ports in an OFDM symbol containing RSs may be 2×N _RBs , which may mean that the sequence length is 2×N _RBs . Additionally, in such an embodiment, N _RB represents the number of RBs corresponding to the bandwidth and the sequence may be binary or complex. Sequence r(m) can give a complex sequence as

Here, N ^max _RB represents the number of RBs corresponding to the maximum bandwidth in a communication system such as an LTE system, and N ^max _RB may be 110. Additionally, c denotes a PN sequence of length-31 and may be defined by a Gold sequence. If the DM-RS is configured, the following equation may be used.

Here, N ^PDSCH _RBs indicate the number of RBs allocated for a particular WTRU or UE. The sequence length may vary depending on the number of RBs allocated for the WTRU or UE.

In an embodiment, a reference signal (RS) structure may also be provided (eg, in 3GPP LTE-A). For example, to reduce overall RS overhead, DM-RS based downlink transmission may be used (eg, in a communication system such as LTE-A). Additionally, CRS-based downlink transmission may transmit RS sequences for physical antenna ports. Thus, DM-RS based downlink transmission can reduce RS overhead considering that the number of RSs provided or available for DM-RS is equal to the number of layers. Additionally, according to one embodiment, the number of layers may be equal to or less than the number of physical antenna ports. 6 shows an exemplary embodiment of a DM-RS pattern (eg, a DM-RS pattern supporting up to 8 layers) in a PRB of a subframe that may be provided and/or used.

In an embodiment, two CDM groups may be used to multiplex up to 4 layers in each CDM group, for example, allowing up to 8 layers to be multiplexed in this pattern as a maximum. For CDM multiplexing of each CDM group, 4×4 Walsh spreading can also be used.

Additionally, since the DM-RS is used for performing demodulation (eg, limited to being used for performing demodulation), time and/or frequency sparse CSI-RS may be used, for example, for measurement. can be provided. The CSI-RS may be transmitted with a duty cycle such as {5, 10, 20, 40, 80} ms in the PDSCH region. In addition, up to 20 CSI-RS patterns for reuse can be used in a subframe. 7 shows an exemplary embodiment of CSI-RS patterns for reuse according to the number of ports (eg, up to 20 CSI-RS patterns can be reused here). In FIG. 7, the same pattern or shading in which corresponding TX numbers are nested or associated with each other may indicate the same set of REs for CSI-RS configuration.

An Observed Time Difference of Arrival (OTDOA) may also be provided and/or used for positioning in a communication system, such as an LTE system, for example. For OTDOA positioning, a WTRU or UE may receive one or more signals from a reference cell and/or one or more additional cells, e.g., neighboring cells (e.g., between each additional or neighboring cell and a reference cell). ) may measure the OTDOA of these signals, and/or may report such measurements, information or signals to the network. Based on the location of the cells, the time difference between cells (which may be fixed), and/or other information, the network may be determined by means such as trilateration or triangulation (e.g., if the WTRU or UE is in at least three cells measurement) and/or other methods or techniques that may provide location and/or location. The reference cell may or may not be the serving cell, eg of a WTRU or UE. For example, the reference cell may be the serving cell of the WTRU or UE if the WTRU or UE has one serving cell, eg without carrier aggregation (CA). As another example, the reference cell may be a serving cell such as a primary cell (Pcell), which is the case with carrier aggregation, for example. In one embodiment, the time difference of arrival can be measured based on a known signal. For example, (e.g. in the case of LTE), the WTRU or UE may use a cell specific reference symbol (CRS) for such measurements, and/or the WTRU in the case of a cell transmitting a positioning reference signal (PRS), e.g. Alternatively, the UE may use PRS. To perform positioning measurements, a WTRU or UE may receive assistance information or assistance data, such as information related to the cell and/or signal being measured. In the case of OTDOA, auxiliary data may include PRS-related parameters. In an exemplary embodiment, supporting OTDOA by the WTRU or UE may be optional, and the use of CRS or PRS for a given cell may be provided and/or determined by the WTRU or UE implementation.

을 만족시키거나 제공할 수 있다. 예시적인 실시형태에 따르면, N_PRS는 1, 2, 4 및/또는 6 서브프레임이고 파라미터 T_PRS 및 Δ_PRS는 각각 PRS 주기수(periodicity) 및 PRS 오프셋이다. 추가로, PRS 주기수는 160, 320, 640 및/또는 1280 서브프레임이고, PRS 오프셋은 0과 'PRS 주기수 - 1' 즉 PRS 주기수보다 1 적은 수 사이의 값일 수 있다. PRS 대역폭(BW)은 PRS BW가 셀의 부분적 BW(예를 들면, 완전한 또는 전체 BW의 일부) 및/또는 셀의 전체 BW를 점유할 수 있도록 협대역 또는 광대역일 수 있다. BW 값은 예를 들면 6, 15, 25, 50, 75 및/또는 100 자원 블록(RB)을 포함할 수 있다. 일 실시형태에 있어서, PRS가 부분적 BW를 점유하고 있을 때, RB는 그 대역의 중앙에 또는 그 대역 내의 임의의 다른 적당한 위치에 있을 수 있다. 셀의 PRS에 대하여 사용되는, 제공되는, 규정되는 파라미터, 및/또는 PRS를 규정하기 위해 사용되는 파라미터(예를 들면, 이 파라미터는 PRS 정보 및/또는 prs-info라고 부르기도 한다)는 DL 서브프레임의 수(예를 들면, N_PRS); T_PRS 및 Δ_PRS(예를 들면, PRS 주기수 및 오프셋)를 구하기 위해 사용되는(예를 들면, 표 또는 다른 적당한 구조로) PRS 구성 인덱스(예를 들면, 0~4095); PRS BW; PRS 상황(occasion)이 셀에서 뮤팅될 때(예를 들면, 송신되지 않을 때)를 규정하는 PRS 뮤팅 정보 등 중에서 하나 이상을 포함할 수 있다.In an exemplary embodiment, a Positioning Reference Signal (PRS) is transmitted by an eNB so that the eNB can recognize or know the transmission parameters of the cell under its control. For a given cell, a PRS may be specified to be provided or included in N _PRS consecutive downlink subframes for each positioning instance (eg, in the case of PRS positioning), where, for example, N _PRS Among the downlink subframes, the first subframe is

can satisfy or provide. According to an exemplary embodiment, N _PRS is 1, 2, 4 and/or 6 subframes and parameters T _PRS and Δ _PRS are PRS periodicity and PRS offset, respectively. Additionally, the number of PRS cycles may be 160, 320, 640, and/or 1280 subframes, and the PRS offset may be a value between 0 and 'number of PRS cycles - 1', that is, a number less than the number of PRS cycles by 1. The PRS bandwidth (BW) may be narrowband or wideband such that the PRS BW may occupy a partial BW of a cell (eg, complete or part of the entire BW) and/or the entire BW of a cell. The BW values may include, for example, 6, 15, 25, 50, 75 and/or 100 resource blocks (RBs). In one embodiment, when the PRS occupies a partial BW, the RB may be in the center of the band or at any other suitable location within the band. Parameters used, provided, and defined for the cell's PRS, and/or parameters used to define the PRS (for example, this parameter is also referred to as PRS information and/or prs-info) are DL sub number of frames (eg, N _PRS ); a PRS configuration index (eg, 0 to 4095) used (eg, in a table or other suitable structure) to obtain T _PRS and Δ _PRS (eg, PRS cycle number and offset); PRS BW; It may include one or more of PRS muting information defining when a PRS occasion is muted in a cell (eg, when not transmitted).

According to one embodiment, the PRS positioning context may be muted, eg periodically, in the cell. The PRS muting configuration may be defined by a periodic PRS muting sequence with a periodic number of 2, 4, 8 and/or 16 positioning events in an embodiment. The PRS muting information may be provided using a p-bit field for the number of cycles p, where each bit corresponds to a PRS positioning situation in each muting sequence and/or indicates whether the situation is muted or not muted. there is. When a PRS positioning situation is muted in a cell, PRSs may not be transmitted in N _PRS subframes of a special situation in that cell (eg, any N _PRS subframes).

Additionally, when PRS muting information is signaled to the WTRU or UE in positioning assistance data (eg, when PRS muting information is included in positioning assistance data and signaled to each other), the first bit of the PRS muting sequence is zero (eg For example, it may correspond to the first PRS positioning situation starting after the beginning of the system frame number (SFN) where SFN=0), where the SFN may be the SFN of the OTDOA reference cell of the WTRU or UE. .

8 is a diagram illustrating an exemplary embodiment of an architecture that may be used for positioning. According to one embodiment, the architecture shown in FIG. 8 can be used with an LTE communication system, such as the communication system 100 shown in FIGS. 1A and 1C-1E, and can provide positioning for the LTE communication system. there is. As shown in FIG. 8 , the positioning of or by the UE or WTRU may be controlled by an Enhanced Serving Mobile Location Center (E-SMLC). In an exemplary embodiment, communication between the WTRU and the E-SMLC may be point-to-point or transparent to the eNB. A WTRU or UE may communicate with the E-SMLC using a protocol such as LTE Positioning Protocol (LPP) over the control plane or data plane as shown in FIG. 8 . Such communication (eg, communication between a WTRU or UE and an E-SMLC) may be encapsulated in signaling or data between an eNB and a WTRU or UE or between a Secure User Plane Location (SUPL) Location Platform (SLP) and a WTRU or UE. . According to an exemplary embodiment, the eNB may not know what is in the LPP message. Communication between the E-SMLC and the WTRU may go through a Mobility Management Entity (MME) or SLP, where the MME or SLP may communicate directly to/from the appropriate WTRU and may or may not know the content of the communication and may or may not know the content of the communication. and/or may or may not modify carriage. Communications may be enabled via SLP and/or via SUPL bearers if the WTRU or UE is a SUPL Enabled Terminal (SET).

Additionally, information passed or exchanged between the WTRU or UE and the S-SMLC includes the ability of the WTRU or UE to support OTDOA positioning, commands from the E-SMLC to perform OTDOA measurements, which cell is the reference cell for OTDOA, and and/or OTDOA positioning assistance data from the E-SMLC to the WTRU or UE, such as if it is an additional or neighbor cell, and measurement reports from the WTRU or UE to the S-SMLC. Auxiliary data or other exchanged information may include information such as cell ID and/or carrier frequency, and/or PRS information for reference cells and/or additional or neighboring cells. Since PRS transmission is the responsibility of the eNB, the E-SMLC can obtain at least some of the PRS information from one or more eNBs, at which time the communication between the E-SMLC and the eNB can be done through an LPP interface or protocol.

According to example embodiments, one or more modes of transmission may be provided and/or used in a communication system to transmit and/or receive information, data and/or signals. Table 3 shows example embodiments of communication systems (eg, LTE and/or LTE-Advanced systems) that can be used to provide the information and/or signals described herein. The transmission modes (TMs) provided in Table 3 (eg, except for TM-7, 8 and 9 in one embodiment) may utilize CRS for both demodulation and measurement. Additionally, for TM-7 and 8 shown in Table 3, DM-RS may be used for demodulation and CRS may be used for measurement. According to one embodiment, for TM-9 shown in Table 3, DM-RS and CSI-RS may be used for demodulation and measurement, respectively.

Transmission mode in LTE/LTE-A Transmission mode (TM) Transmission method of PDSCH One Single antenna port, port 0 2 transmit diversity 3 Transmit Diversity if the associated class indicator is 1, otherwise large delay CDD 4 Closed-loop spatial multiplexing 5 Multiuser MIMO 6 Closed-loop spatial multiplexing by a single transmit layer 7 A single antenna port, port 0, if the number of PBCH antenna ports is 1; Otherwise transmit diversity 8 If the UE is configured without PMI/RI reporting, a single antenna port, port 0, if the number of PBCH antenna ports is 1; Otherwise transmit diversity

Closed-loop spatial multiplexing if the UE is configured with PMI/RI reporting 9 If the UE is configured without PMI/RI reporting, a single antenna port, port 0, if the number of PBCH antenna ports is 1; Otherwise transmit diversity

Closed-loop spatial multiplexing with up to 8 layer transmission, ports 7-14

According to an exemplary embodiment, channel state information (CSI) feedback may be provided and used. For example, multiple (eg, two) types of reporting channels such as PUCCH and/or PUSCH may be used. The PUCCH reporting channel can provide CSI feedback while allowing limited feedback overhead. The PUSCH reporting channel can tolerate a large amount of feedback overhead with lower reliability. The PUCCH report channel can be used for periodic CSI feedback of coarse link adaptation and/or PUSCH reports can be triggered irregularly for finer link adaptation.

Reporting mode in LTE/LTE-A scheduling mode Periodic CSI reporting channel Aperiodic CSI reporting channel frequency non-selective PUCCH frequency selective PUCCH PUSCH

A downlink control channel may also be provided and/or used. The downlink control channel can occupy the first 1-3 OFDM symbols in each subframe depending on the overhead of the control channel. This dynamic resource allocation to handle the downlink control channel overhead allows for efficient downlink resource utilization, which can result in higher system throughput. Various types of downlink control channels are used for downlink control in each subframe, such as PCFICH (Physical Control Format Indicator Channel), PHICH (Physical Hybrid-ARQ Indicator Channel), and/or PDCCH (Physical Downlink Control Channel). It can be transmitted in the channel domain. A downlink control channel resource unit may be defined as four consecutive REs in the frequency domain called REGs (Resource Element Groups) as shown in FIGS. 9 and 10 . 9 shows an exemplary REG definition in a downlink control channel with 2Tx CRS. 10 shows an exemplary REG definition in a downlink control channel with 4Tx CRS. As shown, if the CRS is located in the same OFDM symbol, the REG can be defined in 4 consecutive REs without the CRS. In another embodiment, the Physical Control Format Indicator Channel (PCFICH) is used as described herein. may be provided and/or used. For example, the PCFICH may indicate the number of OFDM symbols transmitted in the 0th OFDM symbol of each subframe and/or used for the downlink control channel in the subframe. Dynamic downlink control channel resource allocation at the subframe level may be possible by using the PCFICH. A WTRU or UE may detect a CFI (Control Format Indicator) from the PCFICH, and a downlink control channel region may be defined in a subframe according to the CFI value. Table 5 shows CFI codewords that can be detected from PCFICH, and Table 6 shows details of downlink control channel resource allocation according to CFI values, subframe types, and system bandwidth. In an embodiment, the PCFICH may be skipped if the subframe is defined as a non-PDSCH supportable subframe and the WTRU or UE is not attempting to detect the PCFICH in the subframe.

CFI Codeword CFI CFI Codeword
<b0, b1, ..., b31> One <0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0 ,1,1,0,1,1,0,1> 2 <1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1 ,0,1,1,0,1,1,0> 3 <1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1,1,0,1 ,1,0,1,1,0,1,1> 4
(reservation) <0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 ,0,0,0,0,0,0,0>

Number of OFDM symbols used for PDCCH subframe Number of OFDM symbols for PDCCH when N ^DL _RB >10 Number of OFDM symbols for PDCCH when N ^DL _RB ≤ 10 Subframes 1 and 6 for frame structure type 2 1,2 2 MBSFN subframes on carriers supporting PDSCH, consisting of 1 or 2 cell-specific antenna ports 1,2 2 MBSFN subframe on a carrier supporting PDSCH, consisting of four cell-specific antenna ports 2 2 Subframes in carriers that do not support PDSCH 0 0 Non-MBSFN subframes configured with positioning reference signals (except for subframe 6 for frame structure type 2) 1,2,3 2,3 in all other cases 1,2,3 2,3,4

In one embodiment, four REGs can be used for PCFICH transmission in the 0th OFDM symbol of a subframe, and the REGs can be uniformly distributed over the entire system bandwidth to take advantage of the frequency diversity gain. The starting point of PCFICH transmission may be different according to physical cell-ID (PCI) as shown in FIG. 11 . The frequency shift of the PCFICH combined with the cell-ID can provide performance of PCFICH detection performance by avoiding PCFICH collisions between multiple neighboring cells while achieving diversity order 4 from its distributed assignment. At the WTRU or UE receiver, the procedure of downlink control channel detection (eg, first procedure) may be to decode the PCFICH to find out the number of OFDM symbols in a subframe. If the downlink control resource is defined by the PCFICH, the PCFICH detection error may result in loss of downlink grant, uplink grant, and/or PHICH reception. The Physical Hybrid-ARQ Indicator Channel (PHICH) is here may be provided and/or used as described in In one embodiment, the PHICH may be used to transmit ACK or NACK corresponding to the PUSCH transmitted in the uplink subframe. The PHICH may be transmitted in a distributed manner across OFDM symbols within the downlink control channel and system bandwidth. The number of OFDM symbols can be specified as a PHICH duration and can be configured through higher layer signaling. The PHICH resource location may change according to the PHICH duration.

및 DM-RS 주기적 편이(n_DMRS)와 같은 업링크 허가에서 자원 정보에 의해 동적으로 규정될 수 있다. 2개의 인덱스 쌍(PHICH 그룹 인덱스: n^group _PHICH, PHICH 시퀀스 인덱스: n^seq _PHICH)은 특정 WTRU 또는 UE에 대한 PHICH 자원을 표시할 수 있다. PHICH 인덱스 쌍(n^group _PHICH, n^seq _PHICH)에서, 각 인덱스는 다음과 같이 규정될 수 있다.12 shows an exemplary PCFICH and PHICH resource allocation (eg, PCFICH and PHICH REG allocation according to PCI). As shown in FIG. 12, multiple PHICH groups may be defined within a cell and a PHICH group may include multiple PHICHs with orthogonal sequences, with the PHICH for a WTRU or UE having the lowest PRB index.

and resource information in uplink grants such as DM-RS cyclic shift (n _DMRS ). Two index pairs (PHICH group index: n ^group _PHICH , PHICH sequence index: n ^seq _PHICH ) may indicate PHICH resources for a particular WTRU or UE. In a PHICH index pair (n ^group _PHICH , n ^seq _PHICH ), each index can be defined as follows.

Here, n ^group _PHICH means the number of PHICH groups available in the system and can be defined as follows.

Here, N _g is 2-bit information transmitted through a physical broadcast channel (PBCH), and this information may be within N _g ∈ {1/6, 1/2, 1, 2}.

Additionally, orthogonal sequences according to spreading factors may also be provided and/or used, for example as shown in Table 7.

Orthogonal sequence according to sequence index and spreading factor Sequence index n ^seq _PHICH orthogonal sequence normal cyclic prefix
N ^PHICH _SF = 4 extended cyclic prefix
N ^PHICH _SF = 2 0 [+1 +1 +1 +1] [+1 +1] One [+1 -1 +1 -1] [+1 -1] 2 [+1 +1 -1 -1] [+j +j] 3 [+1 -1 -1 +1] [+j -j] 4 [+j +j +j +j] - 5 [+j -j +j -j] - 6 [+j +j -j -j] - 7 [+j -j -j +j] -

A physical downlink control channel (PDCCH) may be provided and/or used as described herein. For example, a PDCCH may be defined as one or a plurality of contiguous control channel element (CCE) resources, where one CCE may include 9 REGs. The number of available CCEs (N _CCE ) may be defined as N _CCE = └N _REG /9┘, where N _REG is the number of REGs not specified in PCFICH or PHICH. Table 8-1 shows an exemplary available PDCCH format by definition of a number of contiguous CCEs that can be provided, used and/or supported. As shown in Table 8-1, four PDCCH formats may be supported and/or the number of CCEs according to the PDCCH format may be different. The number of CCEs in the PDCCH format may be referred to as an aggregation level.

[Table 8-1]

Supported PDCCH Formats

In one embodiment, the WTRU or UE may monitor PDCCH candidates and/or blind decode a given number of times (eg, as shown in Table 8-2). The set of PDCCH candidates monitored by a WTRU or UE may be defined as a search space.

[Table 8-2]

PDCCH candidates monitored by WTRU or UE

Aggregation levels {1, 2, 4, 8} may be supported in the WTRU or UE specific search space and aggregation levels {4, 8} may be supported in the common search space. A search space (S ^(L) _k ) at the aggregation level L ∈ {1,2,4,8} may be defined by a set of PDCCH candidates. For each serving cell for which the PDCCH is monitored, the CCE corresponding to the PDCCH candidate (m) in the search space (S ^(L) _k ) may be given as follows.

where Y _k can be defined as described herein, i=0,...,L-1. In the case of a common search space, m'=m. Additionally, in the case of a WTRU or UE-specific search space and a serving cell for which the PDCCH is monitored, m'=m+M ^(L) n _CI if the monitoring WTRU or UE is configured with a carrier indicator field; Here, n _CI may be a carrier indicator field value. Otherwise, if the monitoring WTRU or UE is not configured with a carrier indicator field, then m'=m, where m=0,...,M ^(L) -1 and M ^(L) is in the given search space. This is the number of PDCCH candidates to be monitored. In the case of a common search space, Yk can be set to 0 for the two aggregation levels L=4 and L=8. For a WTRU or UE specific search space (S ^(L) _k ) at aggregation level L, the variable Y _k may be defined by Y _k =(A·Y _k−1 )modD, where Y _{k -1} = n _RNTI ≠0, A = 39827, D = 65537, and k =└n _s /2┘, where n _s may be the number of slots in a radio frame.

As described herein, the PDCCH may be enhanced by transmitting the PDCCH in the PDSCH region along with a WTRU or UE specific reference signal such that beamforming gain, frequency domain ICIC, and/or PDCCH capacity enhancement gain may be achieved and/or improved. (eg, ePDCCH may be provided). 13 shows an exemplary ePDCCH multiplexing (FDM multiplexing) with PDSCH.

및

에 의해 표시될 수 있다.In an exemplary embodiment, PUCCH may be allocated in conjunction with PDCCH. For example, physical resources used for PUCCH may depend on one or more parameters such as N ⁽²⁾ _RBs and/or N ⁽¹⁾ _CSs given by higher layers. Variable N ⁽²⁾ _RB ≥ 0 represents a bandwidth associated with a resource block usable by PUCCH format 2/2a/2b transmission in each slot. Variable N ⁽¹⁾ _CS may indicate the number of cyclic shifts used for PUCCH formats 1/1a/1b of resource blocks used for mixing formats 1/1a/1b and 2/2a/2b. The value of N ⁽¹⁾ _CS may be an integer multiple of Δ ^PUCCH _Shift within the range of {0, 1, ..., 7}, where Δ ^PUCCH _Shift may be provided by a higher layer. In one embodiment, if N ⁽¹⁾ _CS =0 then mixed resource block may not be provided. Additionally, there may be (eg, at most) one resource block in each slot supporting a mix of formats 1/1a/1b and 2/2a/2b. Resources that can be used for transmission of PUCCH formats 1/1a/1b, 2/2a/2b and 3 are each a non-negative index

and

can be indicated by

Mappings to physical resources may be provided and/or used, for example as described herein. In such an embodiment, a block of complex symbols z ^(/p) (i) may be multiplied with an amplitude adjustment factor β _PUCCH to conform to the transmit power P _PUCCH and/or starting with z ^(/p) (0). can be mapped to resource elements in the order of PUCCH may use one resource block in each of two slots of a subframe. Within the physical resource block used for transmission, mapping z ^{(/p) (i) to the resource elements (k, l) of the antenna port (p)} not used for reference signal transmission is the first k, its It can then be in ascending order of l and slot number, starting at the first slot of the subframe. A relationship between the index /p and the antenna port number p may be defined.

A physical resource block used for PUCCH transmission in slot n _s can be given as follows.

이면Here, the variable m may depend on the PUCCH format. For formats 1, 1a and 1b, if

the other side

, otherwise c=3 (normal cyclic prefix) or 2 (extended cyclic prefix). In the case of format 2/2a/2b

, and in the case of format 3

am.

The mapping of modulation symbols to physical uplink control channels is shown in FIG. 14 . In an embodiment in which a sounding reference signal and PUCCH formats 1, 1a, 1b, or 3 are simultaneously transmitted when one serving cell is configured, a shortened PUCCH format can be used, where the last SC-FDMA of the second slot of the subframe is used. The symbol may remain empty.

An FDD HARQ-ACK procedure and/or method for the configured serving cell may be provided. For example, HARQ-ACK transmission on two antenna ports (p∈[p0,p1]) can be supported for formats 1a/1b. For FDD and one configured serving cell, the WTRU or UE is assigned to /p mapped to antenna port p for PUCCH formats 1a/1b as described below (eg, when one or more of the following apply). For HARQ-ACK transmission in subframe n, PUCCH resource n ^(1,/p) _PUCCH can be used.

를 이용할 수 있고, 여기에서 n_CCE는 대응하는 DCI 지정의 송신을 위해 사용되는 제1 CCE(예를 들면, PDCCH를 구성하기 위해 사용된 최저 CCE 인덱스)의 수일 수 있고 및/또는 N⁽¹⁾ _PUCCH는 상위층에 의해 구성될 수 있다. 2개의 안테나 포트 송신의 경우에, 안테나 포트 p₁에 대한 PUCCH 자원은

에 의해 주어질 수 있다.For a PDSCH transmission indicated by the detection of the corresponding PDCCH in subframe n-4, or for a PDCCH indicating a downlink SPS release in subframe n-4, the WTRU or UE has an antenna port p ₀ in subframe n. about

, where n _CCE may be the number of first CCEs (eg, the lowest CCE index used to construct the PDCCH) used for transmission of the corresponding DCI designation, and/or N ⁽¹⁾ _PUCCH can be configured by higher layers. In the case of two antenna port transmission, the PUCCH resource for antenna port p ₁ is

can be given by

For PDSCH transmission in the primary cell when a corresponding PDCCH is not detected in subframe n-4, a value of n ^(1,/p) _PUCCH may be determined according to a higher layer configuration. For a WTRU or UE configured for two antenna port transmissions, the PUCCH resource values are the first PUCCH resource n ^(1,/p) _PUCCH for antenna port p ₀ and the _second PUCCH resource n ^{( 1,/p)} It can be mapped to two PUCCH resources together with _PUCCH . Alternatively, the PUCCH resource value may be mapped to a single PUCCH resource n ^(1,/p) _PUCCH for antenna port p ₀ .

The FDD HARQ-ACK feedback procedure for two or more configured serving cells may be based on, for example, PUCCH format 1b or PUCCH format 3 HARQ-ACK procedure with channel selection HARQ-ACK procedure. HARQ-ACK transmission on two antenna ports (p ∈ [p ₀ , p ₁ ]) can be supported for PUCCH format 3.

In the case of FDD with two configured serving cells and PUCCH format 1b with channel selection, the WTRU or UE selects from A PUCCH resource n ⁽¹⁾ _PUCCH,j on _PUCCH resource n ⁽¹⁾ b(0)b ( 1), where 0≤j≤A-1 and A∈{2,3,4}. HARQ-ACK(j) may indicate an ACK/NACK/DTX response for an SPS release PDCCH or transport block related to serving cell c, where HARQ-ACK(j) and a transport block for A PUCCH resource and / or the serving cell may be given as a table.

A WTRU or UE configured with a transmission mode that supports up to two transport blocks on serving cell (c) responds to a PDSCH transmission by a single transport block or a PDCCH indicating a downlink SPS release associated with serving cell (c). The same HARQ-ACK response can be used for .

Additionally, the WTRU or UE may, in accordance with one or more embodiments described herein (eg, one or more of the exemplary embodiments below), A PUCCH resource associated with HARQ-ACK(j) n ⁽¹⁾ _PUCCH,j can be determined, where 0≤j≤A-1.

For a PDSCH transmission indicated by detection of a corresponding PDCCH in subframe n-4 of the primary cell, or for a PDCCH indicating a downlink SPS release in subframe n-4 of the primary cell, the PUCCH resource is n ⁽¹⁾ _PUCCH,j =n _CCE +N ⁽¹⁾ _PUCCH , and for a transmission mode supporting up to two transport blocks, PUCCH resource n ⁽¹⁾ _PUCCH,j+1 is n ⁽¹⁾ _{PUCCH,j +1} = n _CCE +1+N ⁽¹⁾ _PUCCH , where n _CCE is the number of primary CCEs used for transmission of the corresponding PDCCH and N ⁽¹⁾ _PUCCH is configured by higher layers can

For PDSCH transmission in the primary cell when the corresponding PDCCH is not detected in subframe n-4, a value of n ⁽¹⁾ _PUCCH,j may be determined according to a higher layer configuration. For a transmission mode supporting up to two transport blocks, PUCCH resource n ⁽¹⁾ _{PUCCH,j + 1} may be given by n ⁽¹⁾ _{PUCCH,j + 1} = n ⁽¹⁾ _PUCCH,j + 1.

For PDSCH transmission indicated by detection of the corresponding PDCCH in subframe n-4 of the secondary cell, n ⁽¹⁾ values of _PUCCH,j and n ⁽¹⁾ for transmission modes supporting up to two transport blocks ⁾ The value of _PUCCH,j+1 may be determined according to a higher layer configuration. The TPC field of the DCI format of the corresponding PDCCH may be used to determine a PUCCH resource value from one of resource values (eg, 4 resource values) configured by a higher layer. For a WTRU or UE configured for a transmission mode that supports up to two transport blocks, the PUCCH resource value may be multiple (eg, two) PUCCH resources (n ⁽¹⁾ _PUCCH,j , n ⁽¹⁾ _{PUCCH ,j+1} ). In other cases, a PUCCH resource value may be mapped to a single PUCCH resource (n ⁽¹⁾ _PUCCH,j ).

Resource allocation in a carrier aggregation context may be provided. In the case of ePDCCH transmission, both localized and distributed resource allocation can be implemented to better support UEs with different channel conditions in a cell. Localized resource allocation allows frequency selective gain so that the eNB scheduler can increase spectral efficiency by exploiting the channel state information of the WTRU or UE experiencing low Doppler frequencies. Distributed resource allocation provides frequency diversity gain so that reliable PDCCH transmission performance can be achieved without channel state information, which may be suitable for WTRUs or UEs subjected to high Doppler frequencies. Currently, ePDCCH is designed based on a single component carrier and if such a design is used in a multi-carrier network, performance may be limited.

In systems with multiple component carriers, localized resource allocation and distributed resource allocation can be optimized for frequency selective scheduling gain and/or frequency diversity gain. Such an ePDCCH design is focused on a single component carrier and may have limited performance in multi-carrier systems.

Additionally, the WTRU or UE may provide a HARQ-ACK response in subframe n+4 when the WTRU or UE receives the PDSCH in subframe n. Since PDCCH blind detection may require a fraction of the time before starting PDSCH decoding, the PDSCH processing time can be reduced to less than 4 ms. The timing advance may reduce the PDSCH processing time such that the WTRU or UE terminates its decoding process before n+4, for example, assuming the largest transport block size, highest class and/or longest timing advance is considered. . That is, the PDSCH processing time can be further reduced. Since the ePDCCH can be transmitted in the PDSCH region, this reduces the PDSCH processing time and can double the maximum transport block size, for example in a multi-carrier system. A similar processing time reduction can be observed for aperiodic CSI reporting. Aperiodic CSI reporting can be triggered by the downlink control channel, and CSI feedback processing time can be reduced by ePDCCH reception, which can be more serious because the number of component carriers simultaneously becomes larger in the case of CSI reporting. Unfortunately, as described herein, PDSCH processing times and aperiodic CSI reporting processing times in current WTRU or UE receivers are more stringent due to the use of ePDCCH instead of legacy PDCCH, and currently this problem is not possible when using carrier aggregation. may become more important.

Additionally, uplink control channel assignments may be provided. For example, the FDD HARQ-ACK feedback procedure may be based on PUCCH format 1a/1b (eg, dynamically designated PUCCH format 1a/1b) for one configured serving cell (eg, Rel- in single-cell operation, such as 8 or R8). In case of 2 or more DL serving cells for FDD, PUCCH feedback is PUCCH format 1b with channel selection (eg, dynamically designated PUCCH format 1b) (eg, when using 2 DL serving cells) or PUCCH format 3 (eg, semi-statically configured PUCCH format 3) (eg, when using 3 or more configured serving cells) may be used together with ARI. For TDD (eg, Rel-10 TDD), single cell operation may be based on PUCCH format 1 with channel selection (eg, dynamically specified PUCCH format 1). PUCCH format 1 with channel selection (eg, when using two or more DL serving cells) and/or PUCCH format 3 or PUCCH F3 may be used as a function of RRC configuration.

In one embodiment, with the dynamically derived PUCCH resource, in the case of DL designation or single carrier operation received in the primary serving cell with DL carrier aggregation and the corresponding PDCCH in subframe n-4 of the primary cell For a PDSCH transmission indicated by detection, and/or for a PDCCH indicating a downlink SPS release in subframe n-4 of the primary cell, the PUCCH resource is n ⁽¹⁾ _PUCCH,j = n _CCE + N ⁽¹⁾ _PUCCH , and/or PUCCH resource n ⁽¹⁾ _PUCCH,j+1 in the case of a transmission mode supporting up to two transport blocks is n ⁽¹⁾ _PUCCH,j+1 = n _CCE + It can be given by 1+N ⁽¹⁾ _PUCCH , where n _CCE can be the number of primary CCEs used for transmission of the corresponding PDCCH and N ⁽¹⁾ _PUCCH can be configured by higher layers. For embodiments with PUCCH format 3, the PUCCH index may be preconfigured via RRC, and/or for a given DL subframe n-4, the corresponding PUCCH index in UL subframe n is the DL of Scell It can be derived from the ARI carried in the TPC field of the specified message.

PUCCH resources to users or UEs (or WTRUs) decoding DCI using ePDCCH, which can be difficult with multiple carriers, since the structure and/or resource regions of ePDCCH are different from those of legacy PDCCH in case of single-carrier mode of operation. A PUCCH resource allocation mechanism may be specified to allocate. Additionally, in the case of DL carrier aggregation, the PUCCH resource allocation mechanism allows a user (or WTRU) decoding ePDCCH on at least one DL serving cell to transmit scheduled DL data on a primary serving cell and one or more secondary serving cells. It can be used to enable transmission of corresponding ACK/NACK information.

Frame structure 2 TDD support may also be provided. In a TDD system, PDSCH may be transmitted in the PDSCH region of a downlink subframe and/or in the PDSCH region of a subframe (eg, DwPTS). In DwPTS (e.g., a downlink pilot time slot where multiple OFDM symbols are reserved for downlink transmission in a particular subframe), the available number of OFDM symbols for PDSCH transmissions may be limited and/or It may change depending on the configuration. Since legacy PDCCHs can be transmitted together in the same subframe, the embodiment of ePDCCH transmission can be presented separately.

If multiple component carriers are configured with different DL-UL subframe configurations in a TDD system, downlink control channels may not be supported for certain downlink subframes of the secondary cell when using cross carrier scheduling, for example. This may lead to waste of downlink subframes in the secondary cell. Due to the scarce number of OFDM symbols in DwPTS and/or the variable number of OFDM symbols for PDSCH transmissions, ePDCCH transmissions in subframes may now be required (e.g., as described below) or specific WTRU or UE behavior can be specified to help avoid errors (eg as described below).

PDCCH fallback may be provided. For example, when the ePDCCH is supported by the legacy PDCCH of the network, the WTRU or UE can be configured for a specific PDCCH type via higher layer signaling. In such an embodiment there may be an obscurity period where the eNB scheduler does not know whether the WTRU or UE is monitoring the RRC signaled PDCCH type. A PDCCH fallback transmission that may be received by a WTRU or UE regardless of configured PDCCH type may be specified to avoid resource waste and/or unexpected WTRU or UE behavior. In such an embodiment, if the WTRU or UE is configured between the legacy PDCCH and the ePDCCH in a semi-static manner by higher layer signaling, the WTRU or UE should be able to continuously receive the ePDCCH continuously during the configuration process.

A resource collision may also occur between PRS and ePDCCH. For example, when ePDCCH is used in a cell, PRSs transmitted by the cell may overlap or collide with certain REs of the ePDCCH transmission. When the PRS BW overlaps with the ePDCCH transmission BW, the PRS transmission may collide with the DM-RS of the ePDCCH transmission. An example of this collision is shown in FIG. 15 . As shown in FIG. 15, V shift may be zero. This overlap is currently so severe that it may cause performance degradation to such an extent that the WTRU or UE cannot properly decode the ePDCCH. The eNB is responsible for determining whether a WTRU or UE transmits a PRS because the WTRU or UE's support for OTDOA, performance of relevant measurements, and/or knowledge of the PRS information is based on, for example, transparent communication between the WTRU or UE and the E-SMLC. You may not know if you are aware of it. Additionally, systems and/or methods may be provided for handling and/or avoiding such collisions.

As described herein, a system and/or method may be provided for providing an ePDCCH that may be used with multiple carriers. For example, a resource definition or description such as ePDCCH resource configuration may be provided. In the ePDCCH resource configuration, the resource element (RE) of the subframe does not collide with downlink antenna ports (eg, reference signals) of 0 to 22 except for antenna ports {4, 5}; not occupied by PCFICH, PHICH and/or PDCCH; not used for PSS/SSS and/or PBCH; not configured for muted REs (eg, zero power CSI-RS, ABS, null REs); not used for PDSCH; not used for PMCH of configured MBFSN subframes; and/or an ePDCCH that can be used for the above purpose but can be distinguished by providing a mutually orthogonal pattern for both the ePDCCH and the non-ePDCCH (e.g., here as described).

Resources configured for FDD and TDD (eg, on a single DL carrier) may also be provided. For example, a subset of physical resource blocks (PRBs) (also referred to as PRB-pairs or RBs) in a subframe can be configured for ePDCCH transmission, and the ePDCCH resources are broadcast channels (e.g., MIB, SIB-x) and/or higher layer signaling (eg, RRC, MAC, etc.) to the WTRU or UE. A subset of PRBs may be continuous PRBs or distributed PRBs. If the system bandwidth is 5 MHz (eg, then 25 PRBs are available, N ^max,DL _RB =25), then a subset N ^ePDCCH _RBs of PRBs for ePDCCH can be configured, where N ^ePDCCH _RBs < N ^max,DL _RB . 16 shows an example of an ePDCCH multiplexed with a PDSCH when an ePDCCH resource is allocated in a subframe. An ePDCCH at the PRB level multiplexed with the PDSCH may be used (eg, as shown).

In an embodiment, the ePDCCH PRB may be reserved to further simplify ePDCCH reception and/or reduce blind decoding complexity, for example. Additionally, the ePDCCH PRB may be configured at the PRB-pair level and may include one or more of the following. resource allocation type 0, which can be, for example, a bitmap-based indication by resource block group (RBG), where RBG can be defined according to system bandwidth; resource allocation type 1, which can be a bitmap-based representation by RBG subset; A resource allocation type of PDSCH transmission may be used, including resource allocation type 2, which may be contiguous resource allocation (eg, may be given a starting RB number and/or length). The resource allocation type of the ePDCCH resource may differ depending on the ePDCCH mode (eg, distributed and localized transmission). For example, resource allocation type 0 can be used for localized transmission and resource allocation type 1 can be used for distributed allocation, and/or RBs for localized and distributed transmission can overlap. That is, PRB-pairs can be used for both local and distributed transmission. In addition, bitmap indication per PRB-pair level may be used, where a bitmap per PRB-level may be provided to indicate ePDCCH resources using N _DL,PRB bits, N _DL,PRB being down The number of PRB-pairs in the link system can be indicated. In embodiments, predefined PRBs may also be used. For example, multiple PRB-pair subsets may be specified for the ePDCCH and/or subset numbers may be advertised to the WTRU or UE. Each PRB-pair subset may contain one or more numbers of PRB-pairs, and PRB-pairs within a PRB-pair subset may be mutually orthogonal to other PRB-pair subsets. At least one PRB-pair may be used without configuration. The PRB-pair subset may be used for a common search space, or may be used for a first PRB-pair subset of a WTRU or UE specific search space. The subset number may be dynamically advertised to the WTRU or UE. For example, a subset number may be indicated in each subframe in which a WTRU or UE monitors or receives an ePDCCH. A predefined PRB may be used for a common search space. A configuration based PRB may be used for WTRU or UE specific search spaces. The ePDCCH PRB embodiments described herein may be used per ePDCCH resource set when multiple sets of ePDCCH resources are configured for either a WTRU or a UE. The ePDCCH resource set and the ePDCCH region may be used interchangeably.

According to an exemplary embodiment, a WTRU or UE may have special behavior for monitoring the ePDCCH based on a given ePDCCH indication. For example, ePDCCH resources may be advertised to the WTRU or UE via broadcast channels and/or RRC signaling. A WTRU or UE may monitor ePDCCH within its search space, which may be within the PRB subset configured for ePDCCH. A subset of PRBs may be notified to the WTRU or UE by dynamic indication in an implicit or explicit manner. For example, an indication bit may be transmitted in a subframe and/or a DM-RS scrambling sequence may indicate which subset of PRBs configured for ePDCCH may be used. The ePDCCH resource may be advertised to the WTRU or UE by an ePDCCH resource index (ERI) from a set of ePDCCH configurations, and/or the ERI may be advertised by higher layer signaling or subframe index and/or SFN; cell ID; and/or RNTI (eg, C-RNTI, P-RNTI, SI-RNTI). A WTRU or UE may be informed about the type of ePDCCH resource, such as “system ePDCCH resource” and/or “WTRU or UE specific ePDCCH resource”. WTRU or UE behavior related to this ePDCCH resource type may include one or more of the following: The WTRU or UE may receive system ePDCCH resource information via a broadcast channel or higher layer signaling. The WTRU or UE may receive WTRU or UE specific ePDCCH resource information from higher layer signaling. The WTRU or UE-specific ePDCCH resource may be the same as the system ePDCCH resource. The WTRU or UE-specific ePDCCH resources may be a subset of system ePDCCH resources in the time and/or frequency domain. For example, a subset of PRBs in a subframe and/or a subset of temporal subframes/frames may be WTRU or UE specific ePDCCH resources. In an embodiment, a WTRU or UE may not receive (eg, not assume that it does) a PDSCH on a system ePDCCH resource that is not on a WTRU or UE specific ePDCCH resource. A WTRU or UE may receive (eg, assume to receive) a PDSCH on a system ePDCCH resource that is not on a WTRU or UE-specific ePDCCH resource. A WTRU or UE may receive (eg, assume to receive) a PDSCH in a WTRU or UE specific ePDCCH resource if the ePDCCH is not transmitted in an ePDCCH PRB-pair.

According to an exemplary embodiment, an ePDCCH PRB may consist of multiple phases, such as long-term or short-term ePDCCH resources. For example, a long-term ePDCCH resource may be defined in a semi-static manner and/or a short-term ePDCCH resource may be defined in a dynamic manner within a long-term ePDCCH resource. In addition, long-term ePDCCH resources, cell-specific ePDCCH resources, semi-static ePDCCH resources, temporary ePDCCH resources, and/or higher layer configuration type ePDCCH resources may be used interchangeably.

In an embodiment, a long-term ePDCCH resource may be a set of PRB-pairs within the system bandwidth. Resource allocation type 0, 1 or 2 may be used to indicate a set of PRB-pairs as long-term ePDCCH resources. A number of bits (eg, N ^max,DL _PR ) may be used for bitmap-based allocation to support flexibility (eg, full flexibility). The resource allocation of long term ePDCCH resources may be informed to the WTRU or UE via broadcast or higher layer signaling. The WTRU or UE may know or infer that some of the long-term ePDCCH resources (eg, PRB-pairs) may be used for PDSCH transmission. If the PDSCH resource allocation conflicts with the long-term ePDCCH resource but not with the short-term ePDCCH resource, the WTRU or UE may know or assume that the PDSCH may be transmitted on that resource. If the PDSCH resource allocation conflicts with both the long-term ePDCCH resource and the short-term ePDCCH resource, the WTRU or UE may assume that the PDSCH is transmitted on that resource and/or cannot rate-match around that resource.

Short-term ePDCCH resources may be termed WTRU or UE-specific ePDCCH resources, dynamic ePDCCH resources, per-subframe ePDCCH resources, and/or L1 signaling-based ePDCCH resources. Short-term ePDCCH resources may be a subset of long-term ePDCCH resources. A subset of ePDCCH resources may be indicated in each subframe so that the eNB can change the subset of ePDCCH resources from one subframe to another.

Indication of short-lived ePDCCH resources may be based on explicit signaling. Explicit signaling may include one or more indication bits transmitted in the same subframe and/or the location of the indication bits may be fixed. According to an exemplary embodiment, the fixed location may be the lowest index of a PRB-pair configured for long-term ePDCCH resources. The fixed location may be predefined regardless of long/short term ePDCCH resources. For example, the lowest index of a PRB-pair may be within the system bandwidth. The fixed location may be based on distributed transmission.

Indication of short-lived ePDCCH resources may be based on implicit signaling. Implicit signaling may be a PRB-pair of DM-RS configured as a short term ePDCCH resource scrambled with a specific scrambling code known to the eNB and/or WTRU or UE. Therefore, the WTRU or UE can discover the short-term ePDCCH resource by checking the long-term ePDCCH resource with a specific scrambling code. When the WTRU or UE finishes discovering (eg, determining) short-term ePDCCH resources, a WTRU or UE-specific search space may be defined for the short-term ePDCCH resources. Therefore, the WTRU or UE may monitor the ePDCCH within the WTRU or UE specific search space. Short term resources may be configured in a WTRU or UE specific manner. A WTRU or UE may assume that a PDSCH is not transmitted on a PRB-pair configured for e.g. a long-term ePDCCH resource even if the PRB-pair is not within a short-term ePDCCH resource. Short-term resources may be configured in a cell-specific manner. A WTRU or UE may receive the PDSCH of a PRB-pair configured for a long-term ePDCCH resource, e.g., if the PRB-pair is not within the short-term ePDCCH resource.

A plurality of ePDCCH resource sets are provided or described herein and/or a subset of the ePDCCH resource sets may be used in a subframe. The number of ePDCCH resource sets may be configured by the eNB. The number of ePDCCH resource sets may be fixed regardless of system configuration. A subset of the ePDCCH resource set may be configured for a specific WTRU or UE as a WTRU or UE specific search space. A subset of ePDCCH resource sets for a particular WTRU or UE may be predefined as a function of C-RNTI and/or subframe number. For example, if N _ePDCCH subsets of ePDCCH resource sets are defined and one of the subsets of ePDCCH resource sets is configured for a particular WTRU or UE, which ePDCCH resource set is assigned to the WTRU or UE using the equation below: You can choose if it can be used for. A subset of the ePDCCH resource set for a particular WTRU or UE may be defined as k=n _RNTI modN _ePDCCH . Table 8-3 shows an example of subset configuration when 4 ePDCCH resource sets are specified. In the table, 'v' indicates which set is included in the subset. Also, k=n _RNTI mod3 can be used in Table 8-3.

[Table 8-3]

Examples of Multiple Subsets of ePDCCH Resource Set

An ePDCCH resource set may include one or more PRB-pairs and/or the number of PRB-pairs per ePDCCH resource set may be fixed. For example, N _set PRB-pairs may be grouped as a set of ePDCCH resources, where N _set PRB-pairs may be contiguous or dispersed across the system bandwidth.

Additionally, an ePDCCH resource set may be configured as a localized ePDCCH resource or a distributed ePDCCH resource. If an ePDCCH resource set is defined as a localized ePDCCH resource, an eCCE in the ePDCCH resource set may be defined as a localized ePDCCH transmission (LeCCE). A plurality of LeCCEs may be specified in one ePDCCH resource set. The REs of LeCCE may be located within a PRB-pair. If an ePDCCH resource set is defined as a distributed ePDCCH resource, an eCCE in the ePDCCH resource set may be defined as a distributed ePDCCH transmission (DeCCE). A plurality of DeCCEs may be specified in the ePDCCH resource set. The REs of DeCCE can be located across two or more PRB-pairs. A DeCCE may contain multiple eREGs, and an eREG may contain multiple REs within a PRB-pair. Multiple eREGs of DeCCE may be transmitted over multiple PRB-pairs within an ePDCCH resource set. A first set of ePDCCH resources may be predefined as distributed ePDCCH resources and/or another set of ePDCCH resources may be configured as either localized or distributed ePDCCH resources.

(여기에서 Ns는 고정된 수 또는 eNB 구성 수임); 집합당 PRB-쌍의 수에 대한 함수는 국지형 및 분포형 ePDCCH와 같은 ePDCCH 송신에 따라 다를 수 있다; 및/또는 룩업 테이블이 N^max,DL _RB에 따라서 N_set에 대하여 규정될 수 있다. N_set의 값은 아래에 나타낸 표 8-4와 다를 수 있다.The number of PRB-pairs per ePDCCH resource set may vary according to system parameters. For example, the number of PRB-pairs per ePDCCH resource set may be defined as a function of the number of RBs (eg, N ^DL _RB ) or system bandwidth, such that N _set =f(N ^DL _RB ). In this case, one or more of the following may apply:

(where Ns is a fixed number or eNB configured number); The function for the number of PRB-pairs per set may differ for ePDCCH transmissions such as localized and distributed ePDCCH; and/or a lookup table may be defined for N _sets according to N ^max,DL _RBs . The value of N _set may be different from Table 8-4 shown below.

[Table 8-4]

Number of PRB-pairs according to system bandwidth (N _set )

In one embodiment, a fixed N _set of values may be used for a common search space and multiple N _sets of values may be used for a WTRU or UE specific search space. The values of the plurality of N _sets for the WTRU or UE-specific search space may be changed according to at least one of system bandwidth, subframe number and/or number of SFNs, and/or configuration parameters by broadcast or higher layer signaling.

Among the plurality of ePDCCH resource sets, a subset may also be selected explicitly (eg using one or more indication bits). For example, one or more indication bits may be transmitted in the PDCCH region of the same subframe. In this embodiment, at least one of PCFICH or DCI of the PDCCH region may be transmitted for indication bit transmission. The PCFICH of the PDCCH region may be used to indicate how many ePDCCH resource sets can be used. In this case, the number of OFDM symbols of the PDCCH may be defined as following the same number indicated in the PCFICH or configured through higher layer signaling. DCI may be defined and/or transmitted in a common search space. The DCI may include at least one of the number of ePDCCH resource sets and/or a resource allocation index.

One or more indication bits may be transmitted in the same subframe or a previous subframe of the PDSCH region. In this case, an indication channel may be transmitted for indication transmission. An indication channel (eg ePCFICH) may be specified and/or transmitted at a specific location. The location for the presentation channel may be a zero-power CSI-RS or a subset RE of a zero-power CSI-RS. If using zero-power CSI-RS locations, a subset of the ePDCCH resource set may become available within the duty cycle. An indication channel may be specified in the first set of ePDCCH resources. The indication channel may be transmitted over N _set PRB-pairs, for example when N _set PRB-pairs are used for the first set of ePDCCH resources. The presentation channel can be defined at a fixed position in a subframe and/or the position can be changed according to cell ID and/or subframe number. An indication channel may be transmitted in subframe n-1 and/or indication information may be applied in subframe n.

Among the plurality of ePDCCH resource sets, a subset may be implicitly selected. For example, a specific DM-RS scrambling sequence may be used for a subset of the ePDCCH resource set used for ePDCCH transmission in a subframe. A WTRU or UE may detect the set of ePDCCH resources used for ePDCCH transmission in a subframe using, for example, a scrambled sequence for DM-RS. When the WTRU or UE finishes detecting the ePDCCH resource set, the WTRU or UE may discover the WTRU or UE specific search space. A WTRU or UE may initiate blind detection within a WTRU or UE specific search space.

A plurality of ePDCCH resource sets, ePDCCH PRB sets, and/or ePDCCH sets that may be used interchangeably as ePDCCH regions may be implemented. Each ePDCCH resource set may include non-overlapping N _set PRB-pairs, where N _set may have one or more values. In this embodiment, each set of ePDCCH resources may be configured as an ePDCCH localized transmission or an ePDCCH distributed transmission. N _set may additionally or alternatively be configured through higher-layer signaling, pre-defined as a function of system parameters, and/or defined as a combination of system parameters and higher-layer signaling.

A K _set ePDCCH resource set may also be configured for a WTRU or UE, where K _set may have two or more values. In this embodiment, N _set for each ePDCCH resource set can be used independently when the K _set ePDCCH resource set is configured, K _set can be configured through higher layer signaling, and K _set is a broadcast channel (eg For example, MIB, SIB-x), and/or K _set may vary according to SFN/subframe index.

When N _set of each ePDCCH resource set is used independently, one or more of the following may apply: N _set may be larger in localized transmission so that frequency selective scheduling gain is increased while reasonable resource utilization is provided. there is; N _set can be larger in distributed transmission so that the frequency diversity gain is maximized; N _set may be defined as a function of system bandwidth or other cell-specific parameters for at least one ePDCCH transmission (eg, localized or distributed transmission), for example, N _set may be defined as a localized transmission according to system bandwidth Credit is predefined and N _sets can be configured for distributed transmission via higher layer signaling; and/or if K _set is greater than 1, two N _sets may be configured such as N _set,1 and N _set,2, and N _set,1 may be used for an ePDCCH resource set configured as distributed transmission; N _set,2 can be used for all configured ePDCCH resource sets as localized transmission.

The K _set ePDCCH resource set may be configured as a single ePDCCH resource set or a plurality of ePDCCH resource sets. If the WTRU or UE is configured with multiple sets of ePDCCH resources, the WTRU or UE may assume that K _set =2. For this embodiment, if the WTRU or UE is configured with a single set of ePDCCH resources, the set of ePDCCH resources may be configured as localized or distributed ePDCCH transmissions and/or the WTRU or UE may configure the set of ePDCCH resources as distributed transmissions. It can be assumed that it consists of If the WTRU or UE is configured with multiple sets of ePDCCH resources, at least one set of ePDCCH resources is configured as a distributed ePDCCH transmission; One ePDCCH resource set is defined as a primary ePDCCH resource set, and another ePDCCH resource set is defined as a secondary ePDCCH resource set; and/or N _set may vary according to the ePDCCH resource set. For example, the first set may have N _sets =4 and the second set may have N _sets =2.

In an embodiment, the ePDCCH resources may be configured and/or defined differently according to or based on the ePDCCH search space. For example, the ePDCCH common search space may be constructed in a cell-specific manner and the WTRU or UE-specific search space may be constructed in a WTRU or UE-specific manner.

The ePDCCH common search space resource may be configured through at least one of the following. In one embodiment, a minimum set of PRB-pairs may be constructed at specific time and/or frequency locations in a predefined manner. For example, 4 PRB-pairs or 6 PRB-pairs can be defined as the minimum set of PRB-pairs for the common search space, and the center 4 or 6 PRB-pairs of the downlink system bandwidth can be used for the common search space. .

Additionally, in a subframe containing PSS/SSS and/or PBCH, the location of the ePDCCH common search space may be located after the center 6 PRB-pairs if the downlink system bandwidth is greater than 6 PRB-pairs. In this embodiment, 4 or 6 PRB-pairs can be equally split and placed on either side of the central 6 PRB-pairs.

PRB-pairs in the common search space may also be extended in a WTRU or UE specific manner. In this embodiment, the minimum set of PRB-pairs are considered as the first ePDCCH common search space set, and the WTRU or UE specific common search space extensions may be considered as the second ePDCCH common search space set. Thus, two sets of ePDCCH common search spaces can be configured, one configured in a cell specific manner and the other configured in a WTRU or UE specific manner. In such an embodiment, a subset of DCI formats monitored in the common search space may be monitored in the cell specific search space and others may be monitored in the WTRU or UE specific common search space. For example, DCI formats 1A/1B/1C may be monitored in a cell-specific common search space and DCI formats 3/3A may be monitored in a WTRU or UE-specific common search space. Additionally, a WTRU or UE-specific common search space may be configured via higher layer signaling or signaled on a broadcast channel. Further, in an embodiment, two common search space resource sets are configured, a first ePDCCH common search space resource set is predefined at a fixed location and a second ePDCCH common search space resource set is such as MIB or SIB-x. It can be configured through a broadcast channel.

A WTRU or UE-specific search space may be configured through at least one of the following. In an embodiment, a set of WTRU or UE-specific ePDCCH resources may be defined as a set of multiple PRBs. For example, one of {2, 4, 8} PRBs may be configured for WTRU or UE specific ePDCCH resource set via higher layer signaling. Additionally, a bitmap can be used to indicate PRB-pairs configured for a common search space. In an embodiment, up to two WTRU or UE-specific ePDCCH resource sets may be configured per WTRU or UE and the two WTRU or UE-specific ePDCCH resource sets partially or entirely overlap with the PRB-pair.

Also, PRB pairs for the WTRU or UE-specific search space and PRB pairs for the common search space may overlap. In this embodiment, one or more of the following can be applied. A second set of ePDCCH common search space resources may overlap with a set of WTRU or UE-specific ePDCCH resources, where the second set of ePDCCH common search space resources may, for example, be a WTRU or UE-specific common search space or a cell-specific common search space. can If two ePDCCH common search space resource sets are configured, the two ePDCCH common search space resource sets may overlap each other in whole or in part.

An embodiment for resource configuration of TDD in an embodiment of a single DL carrier is described herein. For frame structure 2, several UL-DL subframe configurations and related HARQ-ACK and UL/DL grants can be defined, for example to fully utilize UL/DL resources. Table 9 shows exemplary UL-DL subframe configurations that allow various types of uplink and downlink traffic asymmetry depending on the network environment.

UL-DL subframe configuration Uplink-downlink configuration Downlink-Uplink Turning Point Cycle subframe number 0 One 2 3 4 5 6 7 8 9 0 5ms D S U U U D S U U U One 5ms D S U U D D S U U D 2 5ms D S U D D D S U D D 3 10ms D S U U U D D D D D 4 10ms D S U U D D D D D D 5 10ms D S U D D D D D D D 6 5ms D S U U U D S U U D

In Table 9, 'D' and 'U' represent downlink subframes and uplink subframes, respectively. 'S' denotes a specific subframe that may be used when the subframe configuration is changed from downlink to uplink, for example as a guard time for WTRUs or UEs to prepare to transmit signals. The specific subframe may include DwPTS, UpPTS, and GP, where the DwPTS and UpPTS periods may be the number of OFDM symbols for downlink and uplink transmission, respectively. The remaining times except for DwPTS and UpPTS can be considered as GP. Table 10 shows an exemplary specific subframe configuration.

Configuration of specific subframes in normal CP (length of DwPTS/GP/UpPTS) Specific subframe configuration Normal cyclic prefix on the downlink DwPTS UpPTS Number of DL OFDM symbols Number of SC-FDMA symbols Normal cyclic prefix on the uplink 0 3 6592 T _s

One



2192 T _s

One 9 19760 T _s 2 10 21952 T _s 3 11 24144 T _s 4 12 26336 T _s 5 3 6592 T _s
2


4384 T _s

6 9 19760 T _s 7 10 21952 T _s 8 11 24144 T _s

Since the ePDCCH may be transmitted based on antenna ports 7 to 10, the ePDCCH may not be transmitted in a specific subframe configuration. In such case, WTRU or UE behavior for PDCCH reception may be provided as described herein. For example, the WTRU or UE may assume that the ePDCCH is limited to transmission in normal downlink subframes. The WTRU or UE may assume that the downlink control channel may be transmitted on the legacy PDCCH of a particular subframe regardless of the PDCCH configuration. A WTRU or UE may assume to receive an ePDCCH in downlink subframe n-k that is targeted for a particular subframe n, where k is defined according to the UL-DL subframe configuration and k is the nearest subframe n It can be defined as a downlink subframe. If the WTRU or UE is configured to receive the ePDCCH, the WTRU or UE may skip blind decoding of the ePDCCH in certain subframes. ePDCCH and legacy PDCCH reception can be configured, for example, as shown in the exemplary TDD UL-DL subframe configuration in Table 11, where 'E' and 'L' represent ePDCCH and legacy PDCCH, respectively.

Legacy PDCCH(L)-ePDCCH(E) subframe configuration Legacy PDCCH-ePDCCH Configuration Number of downlink-uplink switching point cycles subframe number 0 One 2 3 4 5 6 7 8 9 0 5ms E L - - - E L - - - One 5ms E E - - - E E - - - 2 5ms E L - - E E L - - E 3 5ms E E - - E E E - - E 4 5ms E L - E E E L - E E 5 5ms E E - E E E E - E E 6 10ms E L - - - E L E E E 7 10ms E E - - - E E E E E 8 10ms E L - - E E L E E E 9 10ms E E - - E E E E E E 10 10ms E L - E E E L E E E 11 10ms E E - E E E E E E E 12 5ms E L - - - E L - - E 13 5ms E E - - - E E - - E 14 reservation 15 reservation

A WTRU or UE may infer that an ePDCCH may or may not be transmitted and/or monitored in a particular particular subframe based on one or more of the following. In the case of downlink normal cyclic prefix (CP), the ePDCCH may be transmitted and/or monitored in the specific subframe configuration {1, 2, 3, 4, 6, 7, 8} of Table 10 (and e.g. , may not be transmitted and/or monitored in configurations 0 and 5 for such TDD and/or downlink normal CPs). A specific subframe configuration in which the ePDCCH can be transmitted may be predefined as other than {1, 2, 3, 4, 6, 7, 8}. For example, an ePDCCH may be transmitted and/or monitored in a DwPTS containing more than m OFDM symbols, where m may be 3, 8, 9 or 10. Additionally, if a particular subframe configuration 0 or 5 is used in a cell, the WTRU or UE behavior for PDCCH reception may be specified in one or more of the following ways. The WTRU or UE is not transmitting and/or monitoring ePDCCH in a specific subframe (e.g., 0 or 5 not included in the specific subframe configuration {1, 2, 3, 4, 6, 7, 8} described above). otherwise the WTRU or UE may monitor the ePDCCH in a specific subframe; The WTRU or UE may assume that an ePDCCH targeting a particular subframe n is transmitted in subframe nk, where k may be defined as the downlink subframe closest to subframe n; The WTRU or UE may assume that the PDCCH is transmitted on legacy PDCCH in a particular subframe; and/or the WTRU or UE may follow the configuration of predefined ePDCCH and legacy PDCCH. If a specific subframe configuration other than 0 and 5 is used in the cell, the WTRU or UE can assume that the ePDCCH is transmitted in DwPTS. There may be a specific subframe where DwPTS is equal to or longer than N _DwPTS [OFDM symbols]. N _DwPTS can be configured by higher layers. N _DwPTS may be fixed as 9 (eg, it may be equivalent to 19760 T _s for normal CP and 20480 T _s for extended CP). If multiple component carriers are configured in TDD mode, , Each component carrier may have a different UL-DL subframe configuration. For example, the Pcell and the Scell may be configured by UL-DL configurations 1 and 2, respectively, as shown in FIG. 17 . 17 shows an exemplary embodiment of carrier aggregation with different TDD UL-DL configurations. In such a case, the downlink subframes of the PCell are not available in subframes 3 and 8 even though the WTRU or UE is expected to receive the PDSCH on the SCell, which means that the WTRU or UE cannot receive the PDCCH on the PCell. Therefore, when cross-carrier scheduling is activated, scheduling restrictions may occur. At least one of the WTRU or UE behaviors described herein may be used when cross-carrier scheduling is active, thereby addressing the above problems. For example, the WTRU or UE may assume that the PDCCH is transmitted on the SCell if the normal downlink subframe is not available on the PCell within the SCell downlink subframe. A WTRU or UE may monitor ePDCCH on the SCell for PDCCH reception regardless of PDCCH configuration. The WTRU or UE may monitor the legacy PDCCH if the WTRU or UE is configured to receive legacy PDCCH in the PCell. A WTRU or UE may monitor legacy PDCCH or ePDCCH according to subframes with predefined PDCCH reception configuration. The WTRU or UE may assume that the PDCCH is transmitted in the SCell if either the normal downlink subframe or a specific subframe is not available in the PCell within the SCell downlink subframe. The WTRU or UE may continue to monitor the PDCCH in a specific subframe if the specific subframe configuration is not 0 or 5. If a specific subframe configuration 0 or 5 is used, the WTRU or UE can assume that the PDCCH is transmitted in the SCell. If a plurality of Scells are configured, the Scell located at the lowest frequency can be regarded as a Pcell for PDCCH reception.

Resource allocation (eg, ePDCCH resource allocation) in a multi-carrier system (eg, multiple DL carriers) may be disclosed, provided, and/or used. In a multi-carrier system, resources for ePDCCH are defined in a PDSCH region, and ePDCCH resources can be multiplexed with PDSCH in an FDM manner. The ePDCCH resource may be configured in one or more of the following ways.

The ePDCCH resource may be limited to the configuration of the primary cell (PCell) if cross-carrier scheduling is activated. In such a case, the WTRU or UE may assume that the ePDCCH is restricted to transmission on the PCell, and the WTRU or UE may restrict monitoring of ePDCCH reception on the PCell. The ePDCCH resource may not be allowed in the secondary cell (Scell). Additionally, the ePDCCH resource in the SCell can be considered a muted RB from the perspective of the WTRU or UE, so the WTRU or UE rate matches the RB if the PDSCH is scheduled on the RB.

Additionally, ePDCCH resources can be configured in a single cell if cross-carrier scheduling is activated. A cell (eg, component carrier) having ePDCCH resources may be configured by higher layer signaling. Cells (eg, component carriers) with ePDCCH resources may be predefined. For example, a broadcast channel (eg, SIB-x) may indicate a cell. Component carriers with ePDCCH may be fixed or may change according to subframes and/or radio frames. If the component carrier with the ePDCCH changes, the WTRU or UE can use the SFN number to implicitly derive which component carrier has the ePDCCH in a particular subframe and/or radio frame.

An ePDCCH resource may be defined as a subset of component carriers equal to or smaller than the configured component carriers for a particular WTRU or UE. Subsets of components may be composed by higher layers. In addition, the subset of component carriers may be predefined including, for example, component carrier number and center frequency. A subset of component carriers may also dynamically change from one subframe to another. Subset patterns can be predefined and/or combined with SFN numbers.

In an embodiment, the ePDCCH and legacy PDCCH may be configured concurrently. In such an embodiment, a subset of component carriers may be configured for ePDCCH and another component carrier may be configured for legacy PDCCH. Therefore, a WTRU or UE can monitor the ePDCCH of a component carrier configured for ePDCCH and the legacy PDCCH of other component carriers.

The ePDCCH frequency diversity mode may be defined interchangeably and is not limited to ePDCCH distributed transmission, ePDCCH frequency diversity scheme, ePDCCH distributed mode, and/or mode-1. In the case of an ePDCCH frequency diversity mode (eg, distributed mode, mode-1, etc.), the resources of the ePDCCH may be distributed across the system frequency bandwidth to achieve a frequency diversity gain. The ePDCCH resource of frequency diversity mode may be configured as described herein. For example, enhanced control channel element (eCCE) and/or enhanced resource group element (eREG) may be distributed over multiple downlink carriers (eg, DL cells), where ePDCCH is {1 , 2, 4, or 8} can be transmitted using eCCE, and eCCE can include N _eREG . Size N can be predefined. If cross-carrier scheduling is activated, the ePDCCH is distributed over the Pcell, otherwise the ePDCCH can be distributed over multiple component carriers (eg, DL carriers). In the case of eCCE aggregation, a WTRU or UE may aggregate eCCE across multiple component carriers (eg, DL carriers) as shown in FIG. 18 for example. 18 shows an exemplary eCCE aggregation across multiple carriers in distributed resource allocation. In the case of eCCE-eREG mapping, the eREG may be distributed across multiple carriers. ePDCCH Mode-1 may be configured within a central 5 MHz (eg, 25 PRB) bandwidth.

The ePDCCH frequency selectivity mode may be defined interchangeably and is not limited to ePDCCH localized transmission, ePDCCH frequency selection scheme, ePDCCH localized mode, and/or mode-2. In the case of ePDCCH frequency selectivity mode (e.g., localized mode, mode-2, etc.), the resources of ePDCCH can be located in one or two RBs depending on the eCCE aggregation level to achieve frequency selection gain. The ePDCCH resource of frequency selectivity mode may be configured as described herein. For example, eCCEs can be located within the same PRB-pair if multiple eCCEs are aggregated. eREGs located within the same PRB-pair and/or neighboring PRB-pairs may be aggregated to form an eCCE. ePDCCH Mode-2 may be configured within a central 5 MHz (eg, 25 PRB) bandwidth.

In a multi-component carrier system, ePDCCH mode-1 (eg ePDCCH frequency diversity mode) and/or ePDCCH mode-2 (eg ePDCCH frequency selectivity mode) may be configured as described herein. For example, a WTRU or UE may monitor ePDCCH mode-2 in PCell and ePDCCH mode-1 in other configured cells if cross-carrier scheduling is not activated. A WTRU or UE may monitor ePDCCH mode-1 and/or ePDCCH mode-2 in the PCell if cross-carrier scheduling is activated. A subset of ePDCCH mode-1 and/or ePDCCH mode-2 resources may be defined as ePDCCH mode-3 spanning multiple PRBs in the center frequency bandwidth.

An ePDCCH resource set may be defined within a cell such that N _set PRB-pairs of the ePDCCH resource set may be located within the cell. For example, a K _set ePDCCH resource set may also be located within a cell. So, when using a plurality of component carriers, N _set and/or K _set may be defined for each cell. Cell can also be used interchangeably as component carrier, Pcell, or Scell. In this case, at least one set among the K _sets of the Pcell may be defined as ePDCCH distributed transmission and/or the K _set may be defined as ePDCCH localized transmission or ePDCCH distributed transmission in the Scell.

Additionally, the ePDCCH resource set may be defined across multiple component carriers such that N _set PRB-pairs of the ePDCCH resource set are located across multiple component carriers. In this case, if the ePDCCH resource set is configured as distributed transmission, N _set PRB-pairs of the ePDCCH resource set are located across a plurality of component carriers; and/or if the ePDCCH resource set is configured as localized transmission, N _set PRB-pairs of the ePDCCH resource set may be located in the same cell.

An enhanced resource element group (eREG) may also be provided as described herein. A minimum resource unit of ePDCCH may be defined and/or referred to as an eREG (enhanced resource element group). An eREG may be formed of a fixed number of REs. An eREG may be formed of a variable number of REs, wherein the number of REs is an eREG number; subframe number and/or subframe type (eg, MBSFN subframe); CSI-RS configuration including zero-power CSI-RS; PRS configuration; It may depend on at least one of SSS/PSS and/or presence of PBCH. eREG includes one or more (e.g., each or a subset) of zero power CSI-RS and non-zero power CSI-RS, SSS/PSS and/or PBCH, PRS, DM-RS, CRS, ePHICH, ePCFICH It can be formed by available REs of a given time/frequency resource grid, such as NxM REs in PDSCH areas that do not

A time and/or frequency resource grid of a PDSCH region (NxM RE) for an eREG may be provided and defined in at least one of the following ways: N and M denote frequency and time RE granularity, respectively; N can be a fixed number between 1 and 12 (in one embodiment, an exemplary fixed number of N can be 1 or 2); N may be configured by broadcast (eg MIB or SIB-x) and/or RRC configuration; N can be different in subframes for localized transmission (ePDCCH mode-1) and distributed transmission (ePDCCH mode-2) (e.g., a small number of N is used for distributed transmission (N _dist ) and and/or a large number N may be used for localized transmission (N _local ), where N _local > N _dist ); M can be defined as 14-N _PDCCH in normal CP and 12-N _PDCCH in extended CP, where N _PDCCH indicates the number of OFDM symbols used for legacy PDCCH and will be indicated by the PCFICH of the subframe. can; M can be defined as a fixed number, such as 11 in normal CP and 9 in extended CP; M may be configured by broadcast (eg MIB or SIB-x) and/or RRC configuration; M can be different in subframes for localized transmission (ePDCCH mode-1) and distributed transmission (ePDCCH mode-2) (e.g., a small number of M is used for distributed transmission (M _dist ) and A large number M can be used for local transmission (M _local ), where M _local > M _dist ).

In one embodiment, an eREG may be formed of a fixed or variable number of REGs, where a REG is four contiguous REs in a PDSCH region used for ePDCCH but not for other purposes, as described herein. can be defined as For example, one eREG can contain 9 REGs, so that an eREG can be similar to a CCE (eg, this can simplify the standardization evolution of terminology from using PDCCH). .

19 shows an exemplary embodiment of an eREG definition. For example, FIG. 19 shows PRB-pairs that can be used for ePDCCH transmission depending on the number of antenna ports (e.g., ports 7-10 on the left side of FIG. 19 and ports 7-8 on the right side of FIG. 19). will be. As shown in FIG. 19, N=1 and M=11 may be used in a subframe that does not include CSI-RS and PSS/SSS. An eREG can span both slots of a PRB-pair, and the number of REs for an eREG can depend on the eREG number resulting from the CRS and DM-RS. For example, depending on the existence of DM-RS and CRS, eREG#n may include 3 REs and eREG#n+2 may include 11 REs (eg, as shown in the left part of FIG. 19). In addition, full FDM-based eREG multiplexing can be used to flexibly utilize the power of unused eREGs. As an example, if eREG#n+7 is not used, its power can be reused to boost up eREG n+2 power.

In one embodiment, eREG resources may be defined in an interleaved manner to randomize RE locations such that the channel estimation performance is the same regardless of the eREG number. Therefore, the WTRU or UE may receive the eREG based on virtual eREG to physical eREG mapping rules.

A fixed number of eREGs may be defined per PRB-pair configured as an ePDCCH resource. For example, 16 eREGs may be defined for each PRB-pair regardless of the configuration of the reference signal, subframe type, CP length, and the like. The eREG may be defined in an interlace manner so that REs other than within the PRB-pair may be periodically allocated for eREGs 0 to 15 in a frequency priority manner. When 16 eREGs are available per PRB-pair, 16×N _set eREGs can be used for an ePDCCH resource set with N _set PRB-pairs.

In an embodiment, eREG subset blocking may be used such that a subset of eREGs in an ePDCCH resource set are blocked and not used to form an eCCE. This allows for improved and better inter-cell interference coordination since overlap-free eREGs can be used between neighboring cells.

For eREG subset blocking, a subset of eREGs in 16×N _sets may be indicated by higher layer signaling, and the subset may not be counted as eREGs. Therefore, real eREGs and virtual eREGs can be defined. A virtual eREG can be used to form an eCCE. Therefore, the number of real eREGs may be equal to or less than the number of virtual eREGs. A subset of eREGs may be predefined as eCCEs, PRB-pairs and/or ePDCCH resource sets. Accordingly, the indication may be based on the number of eCCEs, the number of PRB-pairs, and/or the number of ePDCCH resource sets. Subsets of eREGs may be predefined as a table such that indexes correspond to subsets of eREGs. A bitmap may be used to indicate the subset of eREGs that are blocked.

A subset of eREGs for blocking may be specified as a function of one or more system parameters such as PCI, SFN number, and/or subframe number. In this embodiment, two or more eREG subsets may be predefined with indices and/or the index of each subset may be configured as a function of at least one system parameter. For example, 4 subsets can be defined by the modular J _sub for eREG#n to define the J _sub subset. If J _sub =4, the subset is index-0: subset0={eREG satisfying n mod 4=0}; index-1: subset1={eREG satisfying n mod 4=1}; index-2: subset2={eREG satisfying n mod 4=2}; and/or index-3: subset 3={eREG satisfying n mod 4=3}. When a subset of eREGs for blocking is specified as a function of one or more system parameters, the subset index may be implicitly indicated by at least one system parameter. For example, the subset index may be defined by a modular operation of the cell-ID (eg index-i where i is defined as cell-ID mod 4).

The start symbol of the ePDCCH may be configured as follows (eg, according to the ePDCCH search space or based on the ePDCCH search space). For example, in one embodiment, the starting symbol of a WTRU or UE specific search space may be constructed or defined according to the associated common search space. A related common search space may refer to a common search space monitored in a subframe together with a WTRU or UE specific search space from a WTRU or UE. Additionally, there may be other types (eg two types) of related common search spaces including, for example, a PDCCH common search space and an ePDCCH common search space.

According to an exemplary embodiment, if a PDCCH common search space can be monitored in a subframe along with an ePDCCH WTRU or UE specific search space, one or more of the following may apply and/or may be used or provided. there is. The ePDCCH WTRU or UE-specific search space start symbol may be constructed according to the transmission mode configured for the WTRU or UE. For example, if the WTRU or UE is configured with a legacy transmission mode (eg, TM 1-9), the WTRU or UE may use the CIF in the PCFICH to discover or determine the start symbol of the ePDCCH regardless of the DCI format. You can follow or use that CIF. If the configured transmission mode is another transmission mode (e.g., TM-10 (CoMP transmission mode)), the WTRU or UE may be notified and/or receive the ePDCCH start symbol through higher layers regardless of the DCI format. In one embodiment, the ePDCCH start symbol is a DCI such that if DCI format 2D is used, the WTRU or UE may follow or use the higher layer structured ePDCCH start symbol, otherwise the WTRU or UE may follow or use the CIF of the PCFICH. It can depend on the format.

Additionally, according to an exemplary embodiment, if the ePDCCH common search space is monitored in a subframe along with an ePDCCH WTRU or UE specific search space, one or more of the following may apply and/or provide and/or can be used For example, the ePDCCH WTRU or UE-specific search space start symbol may be the same as the ePDCCH common search space start symbol. Additionally, the ePDCCH WTRU or UE-specific search space start symbol may be constructed as a function of the CFI value of the PCFICH and the ePDCCH common search space start symbol. The ePDCCH WTRU or UE-specific search space start symbol may be independently configured through higher layer signaling regardless of the ePDCCH common search space start symbol. Additionally, in an embodiment, the ePDCCH WTRU or UE specific search space start symbol may be configured according to the configured transmission mode for the WTRU or UE. For example, based on the transmission mode and/or DCI format, the WTRU or UE may estimate the same starting symbol in the ePDCCH common search space or may follow or use a starting symbol value configured by higher layer signaling. In particular, according to one embodiment, if the WTRU or UE is configured with a legacy transmission mode (eg, TM 1-9), the start symbol of the WTRU or UE-specific search space is the first symbol of the ePDCCH common search space within a subframe. start symbol, and if the WTRU or UE is configured for a different transmission mode (eg, TM-10 (CoMP transmission mode)), the WTRU or UE will follow or use the start symbol value configured through higher-layer signaling. can

The start symbol of the ePDCCH common search space may also be constructed or defined based on at least one of the following. According to an exemplary embodiment, a WTRU or UE may implicitly detect the start symbol of the ePDCCH common search space by decoding the PCFICH in each subframe. Additionally, a fixed starting symbol can be predefined by assuming that N _pdcch OFDM symbols can be occupied for legacy PDCCH. So, the start symbol of the ePDCCH common search space may be N _pdcch +1. The number of OFDM symbols for PDCCH may also include N _pdcch =0. For a particular carrier type (e.g., a new carrier type in which the CRS is not transmitted in one or more subframes, e.g., a subframe other than the subframe containing PSS/SSS), the WTRU or UE may use the number of OFDM symbols for the PDCCH. It can be assumed that the number N _pdcch =0. In such an embodiment, the common search space start symbol is broadcast on PBCH or SIB-x so that the start symbol indicated by the broadcast channel can be used for ePDCCH candidate demodulation in the ePDCCH common search space.

로 될 수 있다.The Enhanced Control Channel Element (eCCE) is described herein. Let i be a given subframe, eCCEs including multiple eREGs become N _eREGs (i), and for each eREG j, the number of available REs is K _REs (i,j), and the number of available REs for one eCCE is The total number of REs is

can be

One can think of a first category, where the number of available REs for the jth eREG (e.g., K _REs (i, j)) is attributed to some REs for other purposes, such as reference signals, PDCCHs, PSS/SSSs, etc. and may cause a change in the effective coding rate. For example, one or more of the embodiments described herein may be used to maintain a similar effective coding rate for a given DCI payload.

로서 규정될 수 있다. 미리 규정된 전력 부스팅 규칙으로부터, WTRU 또는 UE는 그 복조 처리를 위해 참조 신호와 ePDCCH RE 간의 전력비를 추정할 수 있다. 고정 수의 N_eREGs가 ePDCCH 송신 유형 및/또는 검색 공간 유형에 따라 별도로 규정될 수 있다. 예를 들면, 국지형 송신에 대해서는 N_eREGs=3을 사용하고 분포형 송신에 대해서는 N_eREGs=4를 사용할 수 있다. 빔포밍 이득 및/또는 주파수 선택성 스케줄링이 국지형 송신에 대하여 달성될 수 있기 때문에 국지형 송신에 대하여 더 작은 N_eREGs를 사용할 수 있다. 분포형 송신은 채널 부호화에 의한 주파수 다양성 이득에 의존할 수 있다. 공통 검색 공간 및 WTRU 또는 UE 특유형 검색 공간에 대하여 다른 N_eREGs 값을 이용할 수 있다. 예를 들면, 공통 검색 공간에 대하여 N_eREGs=6을 사용하고 WTRU 또는 UE 특유형 검색 공간에 대하여 N_eREGs=4를 사용할 수 있다. ePDCCH 검색 공간 내의 eCCE 집성 레벨은 서브프레임에 따라 변할 수 있고, 여기에서 상기 집성 레벨은 특정 서브프레임에 대한 참조 신호 구성으로부터 암묵적으로 도출될 수 있다. 상기 집성 레벨은 양의 정수 N_AL의 함수로서 규정될 수 있다. 예를 들면, WTRU 또는 UE에 대한 검색 공간은 N_AL·{1,2,4,8}로서 규정될 수 있다. 만일 특정 서브프레임에서 N_AL=2이면, WTRU 또는 UE는 집성 레벨 2로 ePDCCH를 모니터링할 필요가 있다. 예를 들면, {1,2,4,8}={2,4,8,16}이다. N_AL은 서브프레임에 따라 상위층에 의해 구성될 수 있고 또는 참조 신호, 방송 채널, 및/또는 동기화 신호를 포함하는 서브프레임의 구성에 따라 암묵적으로 규정될 수 있다. N_AL은 레가시 PDCCH(예를 들면, 레가시 PDCCH가 구성된 경우) 또는 ePDCCH로 운반된 미사용 DCI 비트로 신호될 수 있다.For example, the number of N _REGs can be fixed per eCCE (eg, N _REGs =4), so that the starting point of the eCCE can be easily determined (eg, the starting points of the eCCE can be the same). Since a fixed number of N _REGs can be used per eCCE, available REs can be changed. To increase coverage with a fixed number of N _REGs per eCCE, one or more of the following may be used and/or applied. For example, transmit power per eCCE may be specified as a function of the number of available REs, where the reference number of REs per eCCE may be N _eCCEs . For example, if N _eCCE =36 and the number of available REs is K _REs =18 for a particular eCCE, the additional transmit power added from the original transmit power is

can be defined as From the predefined power boosting rules, the WTRU or UE can estimate the power ratio between the reference signal and the ePDCCH RE for its demodulation process. A fixed number of N _eREGs may be separately defined according to the ePDCCH transmission type and/or search space type. For example, N _eREGs =3 can be used for localized transmission and N _eREGs =4 for distributed transmission. It is possible to use smaller N _eREGs for localized transmission because beamforming gain and/or frequency selective scheduling can be achieved for localized transmission. Distributed transmission may rely on frequency diversity gains by channel coding. Other N _eREGs values may be used for the common search space and the WTRU or UE specific search space. For example, one could use N _eREGs =6 for a common search space and N _eREGs =4 for a WTRU or UE specific search space. An eCCE aggregation level in the ePDCCH search space may change according to subframes, and the aggregation level may be implicitly derived from a reference signal configuration for a specific subframe. The aggregation level may be defined as a function of a positive integer N _AL . For example, the search space for a WTRU or UE may be defined as N _AL ·{1,2,4,8}. If N _AL =2 in a particular subframe, the WTRU or UE needs to monitor the ePDCCH with aggregation level 2. For example, {1,2,4,8}={2,4,8,16}. N _AL may be configured by a higher layer according to a subframe or implicitly defined according to a configuration of a subframe including a reference signal, a broadcast channel, and/or a synchronization signal. N _AL may be signaled as legacy PDCCH (eg, if legacy PDCCH is configured) or unused DCI bits carried on ePDCCH.

For example, a variable number of N _eREGs can be used per eCCE to maintain a similar effective coding rate. Since ePDCCH decoding candidates are based on the eCCE level, the number of available REs for an eCCE can change if a different number of N _eREGs are mapped. If a larger number of N _eREGs are mapped per eCCE, the effective coding rate is lower and as a result the channel coding gain can be increased. That is, a larger number of N _eREGs can be mapped when the number of available REs per eCCE in a specific subframe becomes smaller due to the puncturing of the ePDCCH RE. A variable number of N _eREGs may be defined as described herein. For example, N _eREGs can be configured by the eNB and notified to the WTRU or UE via broadcast channels and/or higher layer signaling. N _eREGs may be independently configured for each subframe according to the duty cycle. For example, 10 ms and 40 ms duty cycles can be used. Two or more N _eREGs may be defined, and one of them may be selected according to the CSI-RS and ZP-CSI-RS configurations. As an example, N ⁰ _eREGs and N ¹ _eREGs may be predefined and one of them may be selected in the following manner: N ⁰ _eREGs may be used when CSI-RS and ZP-CSI-RS are not configured and N ¹ _eREGs can be used when CSI-RS and ZP-CSI-RS are configured.

Since the number of REs for eREG is variable, the number of REs for eCCE may also be variable. eCCE may be defined differently depending on the ePDCCH transmission mode (ie, distributed transmission and localized transmission). For example, N _eREGs =4 can be used for localized transmission and N _eREGs =2 for distributed transmission. In one embodiment, N _eREGs may be configured by the eNB via broadcast (MIB or SIB-x) and/or higher layer signaling.

In another embodiment, N _eREGs may vary from subframe to subframe as described herein. The value of N _eREGs may be changed if the subframe includes CSI-RS and/or zero-power CSI-RS. For example, N _eREGs =4 may be used in a subframe that does not include CSI-RS and/or zero-power CSI-RS, and N _eREGs =6 may be used in a subframe that does not include CSI-RS and/or zero-power CSI-RS. Can be used in frames. The value of N _eREGs may vary depending on the reference signal overhead including the zero-power CSI-RS, and the value of N _eREGs may increase if the reference signal overhead increases. For example, if the reference signal overhead is less than 15% in the PDSCH region of a subframe, N _eREGs =4; If the reference signal overhead is 15 to 20% in the PDSCH area of the subframe, N _eREGs =5; If the reference signal overhead is 20 to 30% in the PDSCH area of the subframe, N _eREGs =6; If the reference signal overhead exceeds 30% within the PDSCH region of the subframe, N _eREGs =7. The reference signal overhead may be defined as "number of PDSCH REs/number of reference signals" or the like. In an embodiment, eREG and eCCE may be the same for certain ePDCCH transmission modes, such as localized transmission of ePDCCH.

Other categories are conceivable, where the number of N _eREGs (i) can be fixed per eCCE, for example such that the starting point of the eCCE is the same. To maintain the effective coding rate for the DCI payload, the number of available REs for the jth eREG (e.g., K _REs (i,j)) is determined by other factors such as reference signals, PDCCHs, and/or PSS/SSS It can be fixed for each eREG by transmitting the ePDCCH in the target RE and applying a special precoding or mutually orthogonal pattern to both the ePDCCH and the non-ePDCCH. At the receiver side after de-precoding by the WTRU or UE, the ePDCCH can be split and a similar effective code rate for a given DCI payload can be maintained.

가 각 CCE에 대하여 유지되도록 적응시킬 수 있다.Assuming that the number of N _eREGs (i) varies from eCCE to eCCE, in order to maintain a similar effective coding rate for a given DCI payload, for example, as described above, the number of available REs for the jth eREG (e.g. , K _REs (i,j)) at the receiver side (e.g., after de-precoding by the WTRU or UE), the ePDCCH can be split and given a DCI A similar effective coding rate for the payload can be maintained. The number of eREGs used to transmit ePDCCH and non-ePDCCH is

can be adapted to be maintained for each CCE.

Additionally, the eCCE definition may be different depending on the ePDCCH search space. In such an embodiment, an eCCE may be defined for a WTRU or UE specific search space and a common search space, respectively, in the following manner. For example, an eCCE definition for a WTRU or UE specific search space may satisfy one or more of the following attributes. 16 eREGs may be defined per PRB-pair regardless of CP length and subframe type. 4 or 8 eREGs can be grouped to form an eCCE according to CP length and subframe type. 4 eREGs can be grouped to form an eCCE for normal CPs with normal subframes and/or normal CPs with specific subframe configurations {3, 4, 8}. In one embodiment, the 8 eREGs are normal CPs with specific subframe configurations {2, 6, 7, 9}, extended CPs with normal subframes and/or specific subframe configurations {1, 2, 3, 5, 6} can be grouped to form an eCCE. Additionally, 4 or 8 eREGs may be grouped to form an eCCE according to CP length, subframe type and/or common search space type. For example, in such an embodiment, the number of eREGs per eCCE for the WTRU or UE specific search space may be 8 if the WTRU or UE monitors the PDCCH common search space in a subframe, and if the ePDCCH common search space If monitored along with this ePDCCH WTRU or UE-specific search space, the number of eREGs per eCCE for the WTRU or UE-specific search space may be 4.

Additionally, an eCCE definition for a common search space may satisfy one or more of the following attributes. In one embodiment, 16 eREGs may be defined per PRB-pair regardless of CP length and subframe type. 4 or 8 eREGs can also be grouped as the same WTRU or UE specific search space. Also, 4 or 8 eREGs may be grouped to form an eCCE according to the number of available REs (eg, n _ePDCCH ). In such an embodiment, the number of available REs may be counted in each subframe within a PRB-pair that does not include PSS/SSS and/or PBCH. Additionally, 8 eREGs may be grouped to form an eCCE if n _ePDCCH is less than a predefined threshold (eg, 104), otherwise 4 eREGs may be used and/or grouped together.

A resource mapping including eREG-eCCE mapping may be provided. For example, an eCCE may be formed with one or more eREGs, and groups of eREGs may be formed differently according to ePDCCH transmission modes (eg, ePDCCH mode-1 and ePDCCH mode-2).

20 shows an exemplary embodiment of eCCE-eREG mapping in ePDCCH according to localized and distributed assignments (eg, when Port-7 and Port-8 are used). For example, eREG can be defined as shown in FIG. 20, where N=1 and M=14 N _PDCCHs can be used. The eREG number may also be defined as at least one of the following: in ascending order from the lowest frequency within the ePDCCH PRB (0 to N _tot (k)-1), where N _tot (k) is the eREG in subframe k. denotes the number of N _tot =N _eRB × M _REG , where M _REG denotes the number of eREGs in a PRB-pair and M _REG =12 as shown in FIG. 20 ; Descending order from the lowest frequency within the ePDCCH PRB (0 to N _tot (k)-1); Random number generation within (0 to N _tot (k)-1) and virtual eREG to real eREG mapping can be defined; The eREG number may be (f,r), where f and r represent the subcarrier index and ePDCCH PRB number within the PRB-pair, respectively, eREG#13 may be represented as eREG(1, 1), and f The range of may be 0 to 11 or 0 to N _eRB -1, and eREG# = r 12 + f.

로서 규정될 수 있다. 도 21은 그러한 예를 보인 것이다(예를 들면, 도 21은 연속 할당에 의한 eCCE-eREG 맵핑의 예시적인 실시형태를 보인 것이다).For eCCE-eREG mapping in a shared PRB, at least one of the following methods (eg, contiguous allocation (Mapping-1), interleaved allocation (Mapping-2), hybrid allocation (Mapping-3), etc.) may be used. there is. For contiguous allocation (mapping-1), N _eREG contiguous eREGs can be aggregated for eCCE definition, so the number of eCCEs is eCCE#n = eREGs#{n N _eREGs , ..., (n+1) ·N _eREGs -1}. For example, if N _eREGs =4 and n=0 then eCCE#0=eREG#{0,1,2,3}. In such an embodiment, the total number of eCCEs (MeCCE) is

can be defined as 21 shows such an example (eg, FIG. 21 shows an exemplary embodiment of eCCE-eREG mapping with contiguous allocation).

For an interleaved assignment (eg, mapping-2), N _eREGs interleaved eREGs can be aggregated for eCCE definition, so the number of eCCEs is eCCE#n = eREGs#{π(n N _eREGs ) , ..., π(n+1)·N _eREGs -1)}, where π(·) denotes an interleaved sequence from 0 to M _eCCE -1. The interleaved sequence π(·) may be generated by N _eREGs ×M _eCCE block interleaver. If N _eREGs =4 and M _eCCE =9, then a 4x9 block interleaver can be defined as shown in FIG. 22 (eg, FIG. 22 shows an example of a block interleaver). For a block interleaver, an interleaved sequence can be generated by writing the sequence to the rows first and reading the columns first. So, the interleaved sequence from the block interleaver shown in Figure 22 could be π=0,9,18,27,1,10,19,28,...,8,17,26,35, which is π (n) = (n·M _eCCE )modN _tot + └n·M _eCCE /N _tot ┘, where n=0,...,N _tot -1. The interleaved sequence π(·) may be generated as a length-N _tot random sequence, where the random sequence is predefined and both the WTRU or UE and eNB know the sequence. For example, column permutation can be used to further randomize the permutation sequence.

For hybrid allocation (e.g. Mapping-3), a subset of contiguous sequences is reserved for localized transmission and another eREG can be used for distributed allocation. For example, a subset of the columns of the block interleaver may be reserved for local transmission as shown in FIG. 23 (eg, FIG. 23 shows a hybrid assignment using a block interleaver), where eCCE# {4, 5, 6, 7} are used for local transmission and the other eCCE is used for distributed assignment. To generate a localized eCCE, N _eREGs contiguous eCCEs can be used. From this operation, the N _eREGs continuous distributed allocation based eCCE can become a localized N _eREGs eCCE. To generate both localized and distributed eCCEs, an eNB may define M _eCCE distributed eCCEs, and reserve N _eREGs contiguous or closed eCCEs for localized eCCEs. Column permutation can be used for distributed assignment parts to further randomize the permutation sequence. From the hybrid allocation shown in FIG. 23, eCCE can be defined as shown in FIG. 24 shows an exemplary embodiment of the coexistence of localized and distributed eCCE.

For eCCE-eREG mapping in separate PRBs, eREGs can be defined independently for localized and distributed transmission. For example, LeREG (local eREG) is defined as 0 to N-1, DeREG (distributed eREG) is defined as 0 to K-1, and contiguous allocation to LeREG (e.g., mapping-1) may be used and/or interleaved allocation (e.g. mapping-2) may be used for DeREG. For eCCE-eREG mapping in a separate PRB, eREG is defined for the limited case of distributed transmission and eCCE can be a minimum resource unit for localized transmission.

The eCCE-eREG configuration may be at least one of the following: eCCE assignment (eg, Mapping-1, Mapping-2, or Mapping-3) is predefined, and the mapping method is a subframe index and/or SFN The mapping method may be configured by higher layer signaling, and the mapping method may be different depending on the ePDCCH PRB-pair. According to an exemplary embodiment, if N _eRBs are available for ePDCCH transmission, a subset of N _eRBs can use mapping-1 and other ePDCCH PRB-pairs (eg, the rest of the ePDCCH PRB-pairs) can use mapping-1. -2 is available. In this embodiment, N _eRB may be separately defined for each mapping method.

If 16 eREGs are available per PRB-pair and one eCCE is defined by a grouping of 4 eREGs, 4 eCCEs can be used for ePDCCH local transmissions since eCCEs can be defined within a PRB-pair for local transmissions. may be specified for each PRB-pair. In one embodiment, 4 contiguous eREGs out of 16 eREGs can be grouped to form a localized eCCE. The eCCE-eREG mapping rule may be the same in each PRB-pair configured as an ePDCCH resource. It is possible to use 4 consecutive eREGs within a PRB-pair with the same starting point regardless of the cell. For example, the eREG-eCCE mapping rule can be as follows for each cell: eCCE(n) = {eREG(k), eREG(k+1), eREG(k+2), eREG(k+ 3)}; eCCE(n+1) = {eREG(k+4), eREG(k+5), eREG(k+6), eREG(k+7)}; eCCE(n+2) = {eREG(k+8), eREG(k+9), eREG(k+10), eREG(k+11)}; and/or eCCE(n+3) = {eREG(k+12), eREG(k+13), eREG(k+14), eREG(k+15)}. Consecutive 4 eREGs within a PRB-pair with different starting points can be used. The starting point of the eREG may be defined as a function of at least one system parameter such as a configuration through higher layer signaling or a physical cell ID and number of subframes/SFNs. In the examples below, the offset can be configured through higher layer signaling or specified as a function of at least one system parameter. For example, eCCE(n) = {eREG(k+i+offset)mod16), i=0,1,2,3}; eCCE(n+1) = {eREG(k+4+i+offset)mod16), i=0,1,2,3}; eCCE(n+2) = {eREG(k+8+i+offset)mod16), i=0,1,2,3}; and/or eCCE(n+3) = {eREG(k+12+i+offset)mod16), i=0,1,2,3}.

Further, in one embodiment, out of the 16 eREGs, 4 mutually exclusive eREGs may be grouped to form an eCCE, so that 4 eCCEs may be defined per PRB-pair and each eCCE may contain 4 mutually exclusive eREGs. there is. Four mutually exclusive eREGs can be selected using one or more embodiments described herein to form an eCCE. For example, interleaved mapping can be used for eREG-eCCE mapping. The eREG-eCCE mapping may be based on a block interleaver (eg, interlaced mapping). The following is an example of eREG-eCCE mapping: eCCE(n) = {eREG(k), eREG(k+4), eREG(k+8), eREG(k+12)}; eCCE(n+1) = {eREG(k+1), eREG(k+5), eREG(k+9), eREG(k+13)}; eCCE(n+2) = {eREG(k+2), eREG(k+6), eREG(k+10), eREG(k+14)}; and/or eCCE(n+3) = {eREG(k+3), eREG(k+7), eREG(k+11), eREG(k+15)}. Interleaved mapping can be used for eREG-eCCE mapping based on a random interleaver. Interleaved sequences can be predefined or configured through higher layer signaling. If an interleaved sequence per eCCE of a PRB-pair is π ₁ ={0,4,8,12}, π ₂ ={1,5,9,13}, π ₃ ={2,6,10,14} , and π ₄ ={3,7,11,15}, where π _j (j=0,1,2,3) is used to form eCCE(n+j), eCCE(n +j) = {eREG(k+π _j (1)), eREG(k+π _j (2)), eREG(k+π _j (3)), eREG(k+π _j (4))} . Interleaved sequences may be defined as a function of at least one system parameter including physical cell ID, subframe, and/or SFN number.

Antenna port mapping may also be provided and/or used. For example, antenna ports {7, 8, 9, 10} or a subset thereof are used for ePDCCH transmission and antenna ports {107, 108, 109, 110} have time and/or frequency locations with orthogonal cover codes. Can be used interchangeably with antenna ports {7, 8, 9, 10} when identical. In one embodiment, since antenna ports 7-10 can be used for eREG and/or eCCE demodulation, antenna port mapping can be defined according to eREG/eCCE location. 25 shows an exemplary embodiment of antenna port mapping for eREG/eCCE. As shown in FIG. 25, eREG/eCCE may be mapped to an antenna port. 25 also shows that the number of available antenna ports can vary depending on the configuration.

The number of available antenna ports (N _port ) may be defined as described herein. N _port can be semi-statically configured for subframes and ePDCCH PRB-pairs. Therefore, the WTRU or UE may assume that the ePDCCH is not transmitted in the RE location for the antenna port in N _port . For example, if N _port =4, then the 24 RE locations in the PRB-pair of Figure 25 are reserved and ePDCCH may not be transmitted at those RE locations. If N _port =2, 12 RE locations are reserved and ePDCCH can be transmitted in RE locations for port-9 and port-10. N _port may be predefined as 4, and the WTRU or UE may assume that the ePDCCH is not transmitted at the RE location for the 4 antenna port. N _port may be different according to the ePDCCH PRB-pair number. For example, N _port =2 may be used in ePDCCH PRB#0 and N _port =4 may be used in ePDCCH PRB#1. N _port may be configured differently according to an ePDCCH PRB-pair having an ePDCCH transmission mode. If ePDCCH PRB#{0, 1, 2} is used for local transmission, N _port =4 can be used for such ePDCCH PRB and N _port =2 can be used for ePDCCH PRB for distributed transmission. . Or vice versa. N _port may also be configured separately for each ePDCCH PRB-pair and/or ePDCCH transmission mode.

Additionally, antenna ports may be allocated for eREG/eCCE based on or in accordance with at least one of the following. A WTRU or UE may assume that the eREG/eCCE associated with the WTRU or UE in “same PRB-pair” is transmitted on the same antenna port. For example, if eREG/eCCE#{n, n+1, n+2, n+3} is used for a WTRU or UE, then the WTRU or UE will send the eREG to one antenna port (e.g. port- 7) can be assumed to be transmitted. The antenna port may be semi-statically configured through higher layer signaling. In such an embodiment, the antenna ports may be the same for the WTRU or UE across each ePDCCH PRB-pair. An antenna port may be defined as the lowest eREG/eCCE index of the same PRB-pair. For example, if eREG/eCCE#{n, n+3, n+6, n+9} is used for a WTRU or UE, the antenna port for eREG/eCCE#{n} is can be used for An antenna port may be specified as a function of the C-RNTI. For example, modulo-4 or 2 in the C-RNTI may indicate an assigned antenna port for a WTRU or UE. The antenna ports may be the same for WTRUs or UEs across ePDCCH PRB-pairs in such embodiments. If modular-4 operation is used, the WTRU or UE may assume that one of antenna ports 7-10 is used for the WTRU or UE, otherwise one of antenna ports 7-8 is used. Antenna ports can be defined as a function of C-RNTI together with CDM groups, and CDM groups can be configured by higher layers. For example, a WTRU or UE may be configured by higher layers to monitor ePDCCH in CDM Group 2, where port-9 and port-10 are available and the C-RNTI for the WTRU or UE is modulo-2 operation. You can mark it to use port-9 later. So, the C-RNTI can indicate which orthogonal cover codes can be used between [+1 +1] and [+1 -1] in the CDM group, and the eNB can select the CDM group. An antenna port may be specified as a function of C-RNTI and PRB-pair index. For example, modulo 4 or 2 of (C-RNTI + PRB index) may indicate the assigned antenna port for the WTRU or UE.

A WTRU or UE may infer that the eREG/eCCE associated with the WTRU or UE is transmitted on the same antenna port by the “precoding resource granularity” (PRG). For example, if a WTRU or UE demodulates multiple eREGs into a PRG, the WTRU or UE can assume that the same antenna port is used for the eREGs in the PRG. The WTRU or UE may assume that the same precoder is used for the antenna ports in the PRG. The PRG size can be different depending on the system bandwidth. Table 12 shows exemplary embodiments of PRG sizes of ePDCCH.

PRG size of ePDCCH System Bandwidth (N ^DL _RB ) PRG size (P') ≤10 One 11 - 26 2 27 - 63 3 64 - 110 2

The PRB size may be 1 for the system bandwidth candidate and the WTRU or UE may assume that each antenna port within that PRB size may use the same precoder so that the channels across antenna ports may be interpolated, for example. For example, if antenna ports 7 and 9 within the PRG size are used for ePDCCH demodulation in a WTRU or UE receiver, the WTRU or UE will assume that the estimated channels from ports 7 and 9 are transmitted on the same virtual antenna port to be interpolated. can An antenna port may be defined as the lowest eREG/eCCE index within a REG. For example, if eREG/eCCE#{n, n+8, n+16, n+24} is used for a WTRU or UE, the antenna port for eREG/eCCE#{n} is for another eREG/eCCE. can be used Antenna ports can also be specified as a function of C-RNTI. For example, modulo-4 or 2 in the C-RNTI may indicate an assigned antenna port for a WTRU or UE. In an embodiment, the antenna ports may also be the same for WTRUs or UEs across ePDCCH PRB-pairs in this case. Additionally, antenna ports may be specified as a function of C-RNTI and PRG index. For example, modulo 4 or 2 of (C-RNTI + PRG index) may indicate the assigned antenna port for the WTRU or UE. It can also be assumed that eCCEs are transmitted on different antenna ports, and the antenna ports of each eREG/eCCE can be defined based on or according to at least one of the following methods described herein. For example, eREG/eCCE locations may be mapped 1:1 to antenna ports according to the number of available antenna ports. If 4 antenna ports are available in the PRB-pair, eREG#{n, n+1, n+2} is mapped to port-7, and eREG#{n+3, n+4, n+5} is mapped to port-8, eREG#{n+6, n+7, n+8} is mapped to port-9, and the rest may be mapped to port-10. If two ports are available, eREG#{n, n+1, n+2, ..., n+5} may map to port-7 and the other eREG to port-8. The associated antenna port number may be defined according to the eREG/eCCE location and aggregation level of the WTRU or UE. If three REGs can be demodulated together, eREG#{n, n+1, n+2} is mapped to port-7, and eREG#{n+3, n+4, n+5} is port-7. It can be mapped to 8. If eREG#{n, n+1, n+2, n+3, n+4, n+5} can be demodulated together then port-7 is used and port-8 is (e.g. no more) eREG It may not be the antenna port for #{n+3, n+4, n+5}. The eREG/eCCE location may be mapped 1:1 to antenna ports according to the number of available antenna ports. Association rules between eREG/eCCE and antenna ports may be configured by the eNB. For example, if 4 antenna ports are available in a PRB-pair, eREG/eCCE#{n, n+1, n+2} is mapped to port-7 and eREG/eCCE#{n+3, n +4, n+5} can be mapped to port-8. For other WTRUs or UEs, eREG/eCCE#{n, n+1, n+2} maps to port-8, and eREG/eCCE#{n+3, n+4, n+6} maps to port-7. can be mapped to

The federation rule may be configured according to at least one of the following embodiments. For example, the eNB may configure association rules via WTRU or UE specific higher layer signaling. Association rules may be configured as a function of the RNTI (eg C-RNTI), and the WTRU or UE may obtain the association rules implicitly. In such a case, there may be different association rules depending on the RNTI type, even for a single WTRU or UE, for example. As an example, a DCI associated with the C-RNTI may use association rule 1 and another DCI associated with the SPS-RNTI may use association rule 2. Modular actions can be used to specify association rules such that the number of association rules (eg, n_association) can be used for modular actions as a function of the RNTI. Association rules for a DCI associated with a specific RNTI may be defined as 'number of association rules = (RNTI) modular n_association'. Association rules may be configured as a function of the RNTI along with other parameters that may include one or more of cell ID, subframe number, and/or SFN. Association rules can also be fixed for a common search space and configurable for a WTRU or UE specific search space.

In one embodiment, the WTRU or UE may assume that a single antenna port configured via higher layer signaling is associated with each eREG/eCCE in localized transmission. A predefined 1:1 mapping between eREG/eCCE to antenna ports can be used for distributed transmission.

Resource element (RE) mapping (eg, puncturing and/or rate matching) may be provided and/or used as described herein. For example, a modulated symbol of DCI after channel coding may be mapped to an ePDCCH RE. Since the ePDCCH RE can be located at the RE location, the mapping rule can be defined in terms of a coding chain. For coding chain aspects, RE mapping rules may include puncturing and/or rate matching as described herein. Puncture and/or rate matching may be provided as follows.

The coded bits (c ₁ , ..., c _N ) are outputs of a channel encoder that takes a DCI payload as an input, where the channel encoder may be a channel code such as a turbo code, a convolutional code, a Reed-Muller code, or the like. . The coded bits may include 16 bits masked with a CRC attachment, e.g., RNTI. The modulated symbols (x ₁ , ..., x _M ) may be outputs of a mapper, and coded bits may be modulated by modulation schemes such as BPSK, QPSK, 16QAM, and 64QAM. Depending on the modulation scheme, the modulated symbol sequence M may be equal to or smaller than N. In RE mapping, the modulated symbols (x ₁ , ..., x _M ) may be mapped to the ePDCCH RE in a frequency-first or time-first manner, for example, where puncturing is performed if the RE of the ePDCCH corresponds to another signal. may imply or provide that the RE's modulated symbol is not transmitted. For example, if x _k (k≤M) is mapped to a specific ePDCCH RE according to a mapping rule and the ePDCCH RE is occupied for another purpose, then x _k is not transmitted and the next mapping can start from x _k+1 . Rate matching may imply or provide that the next mapping to available REs that are not used for other purposes starts from x _k in the same situation. As an example, if 6 modulated symbols {x ₁ ,x ₂ ,x ₃ ,x ₄ ,x ₅ ,x ₆ } are to be transmitted and the ePDCCH REs for x ₂ and x ₄ are occupied for other purposes, Fung In the case of using the processing method, {x ₁ ,x ₃ ,x ₅ ,x ₆ } may be transmitted, and in the case of using the rate matching method, {x ₁ ,x ₂ ,x ₃ ,x ₄ } may be transmitted.

Since the puncturing scheme may lose systematic bits when using convolutional codes and/or turbo codes, in one embodiment, the decoding performance may be worse than rate matching when the code rate is high. there is. Puncturing may provide robustness if the occupied RE information is not synchronized between the eNB and the WTRU or UE. Channel decoding may fail if the occupied RE information is not synchronized between the eNB and the WTRU or UE on a rate matching scheme. Puncturing and rate matching rules based on the purpose of occupied REs may be provided and/or used.

In one embodiment, the rate matching scheme may be used for REs occupied and configured in a cell specific or group specific manner, and the puncturing scheme may be used for REs occupied and configured in a WTRU or UE specific manner. In an example of rate matching, the RE is PDCCH (or PDCCH region), CRS (cell specific reference signal), ePDCCH DM-RS, PRS, PSS/SSS (primary synchronization signal/secondary synchronization signal), and/or PBCH can be occupied by In case of puncturing, the RE can be occupied by CSI-RS, zero-power CSI-RS. In an example of rate matching, an RE may be occupied by CRS, PRS, PSS/SSS, and/or PBCH. In case of puncturing, the RE may be occupied by ePDCCH DM-RS, CSI-RS, and/or zero-power CSI-RS.

Rate matching and puncturing rules may be specified according to the search space. For example, the common search space may use a puncturing scheme and the WTRU or UE-specific search space may use a rate matching scheme to make the common search space more resistant to errors in occupied RE information. It can also be vice versa. In an example of rate matching, each RE may be occupied by another signal in the WTRU or UE-specific search space. In the case of puncturing, each RE may be occupied by another signal in the common search space. Additionally, in the example of rate matching, each RE may be occupied by another signal in the common search space. In the case of puncturing, each RE may be occupied by another signal in the WTRU or UE-specific search space.

According to an exemplary embodiment, rate matching and puncturing rules may be specified according to an ePDCCH transmission scheme or technology, such as localized transmission and/or distributed transmission. For example, rate matching can be applied to each RE occupied by another signal in eCCE for localized transmission and puncturing can be applied to each RE occupied by another signal in eCCE for distributed transmission. can Or vice versa.

Rate matching and puncturing rules can also be specified according to semi-static and dynamic signals. In an example of rate matching, an RE may be occupied by fixed cell specific signals including CRS, PSS/SSS, and/or PBCH. In the case of puncturing, REs may be occupied by semi-static or dynamic configurations including PDCCH, CSI-RS, DM-RS, and/or PRS. In an example of rate matching, an RE may be occupied by semi-static or dynamic configuration including PDCCH, CSI-RS, DM-RS, and/or PRS. In case of puncturing, the RE may be occupied by fixed cell specific signals including CRS, PSS/SSS, and/or PBCH.

In an embodiment, rate matching and puncturing rules may also be defined according to the ePDCCH search space. For example, the rate matching and puncturing rules may be specified differently if the search space is a WTRU or UE-specific search space or a common search space (e.g., for a WTRU or UE-specific search space, a common search space and may apply other rate matching and/or puncturing rules). In the case of a WTRU or UE-specific search space, REs may be configured as ePDCCH WTRU or UE-specific search space resources, where REs collide with PDCCH, CSI-RS, zero-power CSI-RS, and DM-RS. may be rate-matched around.

In the case of a common search space, one or more of the following may be applied. For example (eg, in the case of a RE configured as an ePDCCH common search space resource), a RE located at a CRS location may be neighbor rate matched. In such an embodiment, the number of CRS ports may be fixed as 4 regardless of the number of CRS ports detected in the PBCH. So, when demodulating the ePDCCH common search space, the WTRU or UE may assume that the REs located on CRS ports 0-3 are ambient rate matched. Additionally, in such an embodiment, the WTRU or UE may follow and/or use the number of CRS ports detected on the PBCH for rate matching of the RE located on the CRS port.

Additionally, in the case of a common search space where REs are configured as ePDCCH common search space resources, REs located in CSI-RSs and zero-power CSI-RSs may be punctured. So, if a WTRU or UE is configured with CSI-RS and/or zero-power CSI-RS, the RE at that location may be punctured.

In an exemplary embodiment, for common search space and PDCCH, if the WTRU or UE monitors the PDCCH common search space together with the ePDCCH common search space, the WTRU or UE will be able to perform ambient rate matching to the RE located at the PDCCH location. can Otherwise, the WTRU or UE may be ambient rate matched to REs located in OFDM symbols below the ePDCCH common search space start symbol.

According to one embodiment, a search space design may be provided and/or used as described herein. For example, a search space for a single DL carrier is disclosed. A WTRU or UE may monitor the ePDCCH via blind decoding so that multiple blind decoding attempts can be used per subframe. Candidates for blind decoding attempts from the perspective of the WTRU or UE are hereinafter referred to as search spaces. At least one of two types of search spaces may be defined for the ePDCCH, such as a WTRU or UE-specific search space (USS) and a common search space (CSS). The common search space of ePDCCH may carry DCIs related to UEs and/or groups of UEs in a cell, such as broadcasting/multicasting, paging, group power control, and the like. A WTRU or UE specific search space may carry DCIs for unicast traffic on the uplink/downlink.

From a WTRU or UE perspective, there may be at least two search spaces, and a location relative to a search space may be defined using at least one of the following constructs. In one configuration (eg configuration 1), USS and CSS may both be provided or used on legacy PDCCH, and the WTRU or UE may monitor USS and CSS. In such a configuration, the WTRU or UE may monitor USS and/or CSS in the legacy PDCCH region. This configuration may be the same as or similar to the Release 8 PDCCH configuration. In a further configuration (eg, configuration 2), USS and CSS may both be provided or used on the legacy ePDCCH, and the WTRU or UE may monitor the USS and CSS (eg, the WTRU or UE may USS and/or CSS may be monitored in the ePDCCH region). In another configuration (eg, configuration 3), USS of legacy PDCCH may be provided or used and CSS of ePDCCH may be provided or used (eg, WTRU or UE may provide or use CSS of legacy PDCCH region and/or Alternatively, the USS of the ePDCCH region may be monitored). Additionally, in one configuration (e.g., configuration 4), the USS of ePDCCH may be provided or used and the CSS of legacy PDCCH may be provided or used, where, for example, the WTRU or UE is in the legacy PDCCH region. CSS of and USS of the ePDCCH region can be monitored. Additionally (eg, in configuration 4), the CSS may be shared with legacy UEs. In this case, CSSs of 0 to 15 may be used as the CSS of the legacy PDCCH region. For Configuration 4, CSS can be specified differently. For example, CSSs 16 to 30 of legacy PDCCH may be used as the CSS of a WTRU or UE configured with ePDCCH for USS. In another exemplary configuration (eg configuration 5), USS of ePDCCH may be provided or used and CSS may be split into legacy PDCCH and ePDCCH. According to a further configuration (eg, configuration 6), USS may be split into legacy PDCCH and ePDCCH and CSS of ePDCCH may be provided or used. Also in one configuration (eg configuration 7), both USS and CSS can be split into legacy PDCCH and ePDCCH. In configuration 8, USS is divided into legacy PDCCH and ePDCCH, and CSS of legacy PDCCH may be provided or used.

The search space organization may be defined based on or in accordance with at least one of the following. A single configuration may be predefined and details of the configuration information may be broadcast in MIB and/or SIB-X. The configuration may be predefined such that the WTRU or UE receives the configuration in broadcast information that is at least one of MIB or SIB. The configuration may be RRC configurable such that the WTRU or UE is requested to change the search space according to RRC signaling. The configuration can also be changed according to the SFN and/or subframe number so that the WTRU or UE is implicitly aware of the configuration of each subframe (e.g., configuration information per subframe notified by broadcast or RRC signaling). and/or configuration information for each subframe may be predefined (eg, subframes #0 and #5).

The eCCE aggregation level can be specified the same as the legacy PDCCH, so the aggregation level {1, 2, 4, 8} is specified and the number of blind decoding attempts can total 44 without multi-antenna transmission (e.g., DCI format 4). Unlike the CCE of the legacy PDCCH, the number of REs for the eCCE is variable, and the coding rate of the ePDCCH may vary according to the aggregation level, thus causing ePDCCH coverage variation.

Additional aggregation levels can be added to previous aggregation levels {1, 2, 4, 8} for ePDCCH for finer ePDCCH link adaptation as shown in Table 13. Aggregation levels {3, 5, 6, 7} may be added in case of a WTRU or UE specific search space, {6} may be added for a common search space, for example.

ePDCCH candidates monitored by WTRU or UE Search space (S ^(L) _k ) Number of ePDCCH candidates (M ^(L) ) category Aggregation level (L) size (number of eCCEs)

WTRU or UE specific One 6 6 2 12 6 3 18 6 4 8 2 5 10 2 6 12 2 7 14 2 8 16 2
common type 4 16 4 6 16 4 8 16 2

A WTRU or UE specific search space or a common search space may be defined for the ePDCCH.

Although the number of aggregation levels may be increased, the number of blind decoding attempts may remain the same so as not to increase WTRU or UE receiver complexity. To maintain the number of blind decoding attempts, a subset of aggregation levels can be monitored in a subframe.

Multiple subsets of ePDCCH candidates monitored by the WTRU or UE Search space (S ^(L) _k ) Number of ePDCCH candidates (M ^(L) ) category Aggregation level (L) size (number of eCCEs) subset 1 subset 2 subset 3 subset 4


WTRU or UE specific One 6 6 6 2 12 6 6 6 3 18 6 4 8 2 2 2 2 5 10 6 12 7 14 8 16 2 2 2 2 16 32 2 2
common type 4 16 4 4 6 16 4 8 16 2 2 2 2 16 32 2 2

Additionally, the WTRU or UE may monitor a subset of aggregation levels according to the subset of ePDCCH candidates shown in Table 14. A subset for ePDCCH monitoring may be configured based on or in accordance with at least one of the following: The subset of ePDCCH aggregation level may be configured by broadcast and/or higher layer signaling; Reference signal overhead in ePDCCH resources may implicitly constitute subsets; The subset may be configured differently according to the ePDCCH transmission mode (eg, mode-1 and mode-2); The subset may be configured differently according to the ePDCCH PRB number; etc. The number of ePDCCH candidates per aggregation level may vary depending on the DCI format, ePDCCH resource set, and/or subframe. For example, if aggregation level 1 is used more frequently for DCI format 0/1A, a larger number of ePDCCH candidates for aggregation level 1 than for aggregation level 2 can be used. A larger number of ePDCCH candidates than for aggregation level 1 can be used for DCI format 2C.

Table 14-1 shows an example of a DCI format dependent ePDCCH candidate set, where the number of ePDCCH candidates according to the aggregation level may be different if different DCI formats are used.

[Table 14-1]

DCI format dependent ePDCCH candidate set

A WTRU or UE may attempt to decode 8 ePDCCH candidates with aggregation level-1 when the WTRU or UE monitors DCI format 0/1A. If the WTRU or UE monitors DCI format 2C, the WTRU or UE may attempt to decode the 4 ePDCCH candidates.

The number of ePDCCH candidates for each aggregation level may depend on the DCI format of the WTRU or UE specific search space. Additionally, in one embodiment, the common search space may have an equal number of ePDCCH candidates at each aggregation level regardless of DCI format, for example.

The number of ePDCCH candidates according to the aggregation level {1, 2, 4, 8} may be configured through broadcasting and/or higher layer signaling. In one cell, the ePDCCH candidate may be configured as {6, 6, 2, 2} (eg, same as legacy PDCCH), and in another cell, {2, 10, 2, 2} can be configured. An ePDCCH candidate for an aggregation level may be independently configured according to a DCI format or a group of DCI formats. To reduce signaling overhead, a plurality of ePDCCH candidate sets for aggregation levels may be defined with indication bits, for example as shown in Table 14-2.

[Table 14-2]

ePDCCH candidates for aggregation level

In an embodiment, among the sets of ePDCCH candidates, one or more sets may be, for example {6, 6, 2, 2} for a WTRU or UE specific search space and/or {4, 2} and/or {4, 2} for a common search space. Similarly, it may have the same number of ePDCCH candidates as the legacy PDCCH. One or more sets may not have ePDCCH candidates for a common search space. In this case, the WTRU or UE may monitor PDCCH candidates as a common search space. One or more aggregations may include subsets of aggregation levels that do not have candidates. For example, {8, 8, 0, 0} could be used in this case so that aggregation levels 4 and 8 are not supported in the search space. The total number of blind decoding attempts may remain the same.

ePDCCH candidate definitions may also be provided and/or used as described herein. A WTRU or UE may be configured to monitor ePDCCH in a common search space and/or a WTRU or UE specific search space. In an embodiment, the ePDCCH candidates that the WTRU or UE monitors in a subframe may be defined according to the ePDCCH transmission type.

로서 규정될 수 있고, 여기에서 i=0,...,L-1, m'=m+M^(L) _p·n_CI, 및 m=0,...,M^(L) _p-1이다. M^(L) _p는 ePDCCH 자원 집합(p)의 집성 레벨(L)에 대한 ePDCCH 후보의 수를 표시한다. ePDCCH 자원 집합(p)의 해시 함수일 수 있는 Y_p,k는 Y_p,k = (A·Y_k-1)modD로 표시될 수 있고, 여기에서 Y_p,-1=n_RNTI≠0, A=39827, D=65537 및 k=└n_s/2┘이다.The ePDCCH candidates in the WTRU or UE-specific search space may be specified for ePDCCH localized and/or distributed transmissions as follows, where N _eCCEp,k is the total eCCEs available for ePDCCH resource set p. indicate the number The WTRU or UE-specific search space (S ^(L) _p,k ) for the set of ePDCCH resources (p) is

Can be defined as, where i=0,...,L-1, m'=m+M ^(L) _p n _CI , and m=0,...,M ^(L) _p -1 am. M ^(L) _p indicates the number of ePDCCH candidates for the aggregation level (L) of the ePDCCH resource set (p). Y _p,k, which may be a hash function of the ePDCCH resource set p, may be expressed as Y _p,k = (A Y _k-1 )modD, where Y _p,-1 =n _RNTI ≠0, A = 39827, D = 65537 and k =└n _s /2┘.

로서 규정될 수 있다. ePDCCH 자원 집합(p)에 대한 K_offset,P는 WTRU 또는 UE 특유 방식으로 상위층 시그널링을 통해 구성될 수 있다. K_offset,P는 하기의 파라미터 중 적어도 하나의 함수로서 규정될 수 있다: 집성 레벨(L); ePDCCH 후보 인덱스(m'); 이용가능한 eCCE의 총 수(N_eCCE,k); 및/또는 ePDCCH 자원 집합의 수(K_set).Accordingly, the ePDCCH candidates for the localized ePDCCH resource set may be defined with an offset value (K _offset ) to distribute the ePDCCH candidates over a plurality of PRB-pairs as much as possible. The same ePDCCH WTRU or UE specific search space equation can be used for both localized and distributed ePDCCH. In this embodiment, as an example, the WTRU or UE-specific search space (S ^(L) _p,k ) for a set of ePDCCH resources p consisting of localized ePDCCHs is

can be defined as K _offset,P for the ePDCCH resource set (p) may be configured through higher layer signaling in a WTRU or UE specific manner. K _offset,P may be defined as a function of at least one of the following parameters: aggregation level (L); ePDCCH candidate index (m'); total number of available eCCEs (N _eCCE,k ); and/or the number of ePDCCH resource sets (K _set ).

로서 표현될 수 있고, 여기에서 오프셋(K_offset,P)은 ePDCCH 후보 수(m')의 함수로서 규정될 수 있다. K_offset,P의 정의에 대한 예시적인 실시형태는 다음과 같다. 그러한 예시적인 실시형태(예를 들면, 예시적인 방정식)에 있어서, m' 및 m은 상호 교환적으로 사용될 수 있다.As another example, the offset according to the number of ePDCCH candidates and the aggregation level

It can be expressed as, where the offset (K _offset,P ) can be defined as a function of the number of ePDCCH candidates (m'). An exemplary embodiment for the definition of K _offset,P is as follows. In such exemplary embodiments (eg, exemplary equations), m' and m may be used interchangeably.

을 사용할 수 있다. 그러한 실시형태에 있어서, ePDCCH 자원 집합(p)에 대한 오프셋은

로서 규정될 수 있고, 여기에서 N_eCCE,k,p 및 M^(L) _p는 ePDCCH 자원 집합 특유형이다.According to an exemplary embodiment, if using a plurality of ePDCCH resource sets

can be used. In such an embodiment, the offset for ePDCCH resource set p is

, where N _eCCE,k,p and M ^(L) _p are ePDCCH resource set specific types.

가 사용될 수 있고, 여기에서 Δ_offset,P는 ePDCCH 자원 집합(p)의 오프셋 값을 표시한다. 예를 들면, 제1 ePDCCH 자원 집합은 제로 오프셋 값을 가질 수 있고(즉, Δ_offset,P = 0), 제2 ePDCCH 자원 집합은 미리 규정된 값을 가질 수 있다(예를 들면, Δ_offset,P = 3). 추가의 실시형태에 있어서, 제2 집합에 대한 Δ_offset,P는 하기의 것 중 적어도 하나로서 규정될 수 있다: Δ_offset,P는 상위층 시그널링을 통해 구성될 수 있다. Δ_offset,P는 집성 레벨 및/또는 ePDCCH 자원 집합에 대하여 암묵적으로 구성된 수(즉, eCCE 의 수(N_eCCE,k,p))의 함수로서 암묵적으로 구성될 수 있고/있거나 Δ_offset,P는 서브프레임 번호 및/또는 집성 레벨의 함수로서 구성될 수 있다.In another exemplary embodiment,

may be used, where Δ _offset,P denotes an offset value of the ePDCCH resource set (p). For example, the first ePDCCH resource set may have a zero offset value (ie, Δ _offset,P = 0), and the second ePDCCH resource set may have a predefined value (eg, Δ _{offset, P} = 3). In a further embodiment, Δ _offset,P for the second set may be defined as at least one of the following: Δ _offset,P may be configured through higher layer signaling. Δ _offset,P may be implicitly configured as a function of the aggregation level and/or the implicitly configured number (ie, the number of eCCEs (N _eCCE,k,p )) for the set of ePDCCH resources, and/or Δ _offset,P is may be configured as a function of subframe number and/or aggregation level.

로서 표현될 수 있고, 여기에서 오프셋(K_offset,P)은 ePDCCH 후보 수의 함수로서 규정될 수 있다. 이 실시형태에 있어서, 오프셋은

로서 규정될 수 있다. 추가로, ePDCCH 자원 집합 특유의 오프셋 값(Δ_offset,P)은 하기의 것 중 적어도 하나로서 규정될 수 있다: 제1 ePDCCH 자원 집합에 대하여 Δ_offset,P=0=0이고 제2 ePDCCH 자원 집합에 대하여 Δ_offset,P=1=λ이며, 여기에서 λ는 미리 규정된 양의 정수(예를 들면, λ=3)이고, Δ_offset,P는 상위층 시그널링을 통해 구성될 수 있고, Δ_offset,P는 집성 레벨 및 ePDCCH 자원 집합에 대하여 구성된 PRB의 수의 함수로서 암묵적으로 구성될 수 있고, 및/또는 Δ_offset,P는 서브프레임 번호 및/또는 집성 레벨의 함수로서 구성될 수 있다.As another example, the offset (e.g., depending on the number of ePDCCH candidates and the level of aggregation)

, where the offset (K _offset,P ) may be defined as a function of the number of ePDCCH candidates. In this embodiment, the offset is

can be defined as In addition, the offset value (Δ _offset,P ) specific to the ePDCCH resource set may be defined as at least one of the following: Δ _offset,P=0 =0 for the first ePDCCH resource set and the second ePDCCH resource set For Δ _{offset, P = 1} =λ, where λ is a predefined positive integer (eg, λ = 3), Δ _{offset, P} can be configured through higher layer signaling, Δ _{offset, P} may be implicitly configured as a function of the aggregation level and number of PRBs configured for the ePDCCH resource set, and/or Δ _offset,P may be configured as a function of subframe number and/or aggregation level.

가 사용될 수 있고(예를 들면, 오프셋이 규정된 경우), 여기에서 Φ_offset은 교차 캐리어 스케줄링을 위한 오프셋 값이고 n_CI는 캐리어 표시자 필드 값일 수 있다. Φ_offset은 ePDCCH 자원 집합에 따라 다른 수를 가질 수 있고, 그 경우에 Φ_offset은 Φ_offset,P로 교체될 수 있다. 또한,

를 사용할 수 있다. (예를 들면, 이러한 실시형태에서) Φ_offset은 하기의 것 중 적어도 하나로서 규정될 수 있다: Φ_offset은 미리 규정된 값이고 n_CI는 캐리어 표시자 필드 값일 수 있다; Φ_offset은 상위층 시그널링을 통해 구성될 수 있다; Φ_offset은 집성 레벨 및 ePDCCH 자원 집합에 대하여 구성된 PRB의 수의 함수로서 암묵적으로 구성될 수 있다; Φ_offset은 서브프레임 번호, 캐리어 표시자 값 및/또는 집성 레벨의 함수로서 구성될 수 있다; 및/또는 Φ_offset은 M^(L) _P로서 규정될 수 있고 여기에서 M^(L) _P는 ePDCCH 자원 집합(p)의 집성 레벨(L)에 대한 ePDCCH 후보의 수이다.According to a further example,

may be used (eg, when an offset is specified), where Φ _offset may be an offset value for cross-carrier scheduling and n _CI may be a carrier indicator field value. Φ _offset may have a different number according to the ePDCCH resource set, and in that case, Φ _offset may be replaced with Φ _offset,P . also,

can be used. (eg, in this embodiment) φ _offset may be specified as at least one of the following: φ _offset may be a predefined value and n _CI may be a carrier indicator field value; Φ _offset can be configured through higher layer signaling; Φ _offset can be implicitly configured as a function of the aggregation level and the number of PRBs configured for the ePDCCH resource set; Φ _offset can be configured as a function of subframe number, carrier indicator value and/or aggregation level; and/or Φ _offset may be defined as M ^(L) _P , where M ^(L) _P is the number of ePDCCH candidates for the aggregation level (L) of the ePDCCH resource set (p).

를 사용할 수 있고, 여기에서 Φ_offset은 교차 캐리어 스케줄링에 대한 오프셋 값이고, Δ_offset,P는 ePDCCH 자원 집합(p)에 대한 오프셋이며, n_CI는 캐리어 표시자 필드 값이다. 대안적으로

를 사용할 수 있다. (예를 들면, 이러한 실시형태에서) Φ_offset와 Δ_offset,P는 하기의 것 중 적어도 하나로서 규정될 수 있다: Φ_offset는 미리 규정된 값이고 Δ_offset,P는 ePDCCH 자원 집합 인덱스의 함수로서 구성될 수 있다; Φ_offset는 미리 규정된 값이고 Δ_offset,P는 집성 레벨, 캐리어 표시자 값 및/또는 집성 레벨의 함수로서 구성될 수 있다; 및/또는 Φ_offset와 Δ_offset,P는 둘 다 상위층 시그널링에 의해 구성될 수 있다.As another example,

can be used, where Φ _offset is an offset value for cross-carrier scheduling, Δ _offset,P is an offset for the ePDCCH resource set (p), and n _CI is a carrier indicator field value. alternatively

can be used. (For example, in this embodiment) Φ _offset and Δ _offset,P may be defined as at least one of the following: Φ _offset is a predefined value and Δ _offset,P is a function of the ePDCCH resource set index. can be configured; Φ _offset is a predefined value and Δ _offset,P can be configured as a function of aggregation level, carrier indicator value and/or aggregation level; and/or both Φ _offset and Δ _offset,P may be configured by higher layer signaling.

As another example, K _offset can be predefined as a table. Table 14-3 shows examples of definitions of offset values according to aggregation levels. The exact offset values may vary. The exact offset value may change depending on system configuration and/or ePDCCH resource set configuration.

[Table 14-3]

K _offset according to aggregation level

로서 규정될 수 있고, 여기에서 i=0,...,L-1, m'=m+M^(L)·n_CI, 및 m=0,...,M^(L)-1이고; τ는 미리 규정된 방식으로 고정 값으로서 규정되거나 WTRU 또는 UE 특유 방식으로 상위층 시그널링을 통해 구성될 수 있으며; 및/또는 τ는 WTRU 또는 UE-ID의 함수로서 규정될 수 있다. 예를 들면, τ=n_RNTI이다.Alternatively, if a hash function is not used for localized ePDCCH transmissions, an ePDCCH candidate for an ePDCCH resource may be specified with at least one of the following properties: WTRU or UE-specific search space (S ^(L) _p,k )silver

where i=0,...,L-1, m'=m+M ^(L) n _CI , and m=0,...,M ^(L) -1; τ may be specified as a fixed value in a predefined manner or configured via higher layer signaling in a WTRU or UE specific manner; and/or τ may be specified as a function of WTRU or UE-ID. For example, τ=n _RNTI .

A search space may include a plurality of ePDCCH resource sets. A plurality of ePDCCH resource sets may have multiple PRB-pairs available, and/or the number may be fixed regardless of system bandwidth, cell ID, and/or subframe number, or system bandwidth, cell ID, and/or subframe number. It may change according to the subframe number. The same number of eCCEs are available in the ePDCCH resource set. The number of eCCEs available in an ePDCCH resource set may be fixed regardless of system bandwidth, cell ID, and/or subframe number. The number of eCCEs available in an ePDCCH resource set may vary according to system bandwidth, cell ID, and/or subframe number. The number of eCCEs available in the ePDCCH resource set may be combined with the number of PRB-pairs in the ePDCCH resource set, eg an integer multiple of the number of PRB-pairs in the ePDCCH resource set (e.g., 2 or 4 per PRB). eCCEs can be used with 2×'number of PRB-pairs'). Additionally, the number of eCCEs available in an ePDCCH resource set may change according to configuration.

In other embodiments, the number of available eCCEs may vary depending on the set of ePDCCH resources. For example, the number of eCCEs in the ePDCCH resource set is the number of PRB-pairs configured for the ePDCCH resource set (eg, N _set ), and the CP length, subframe type, duplex mode (TDD or FDD) and/or It may be specified as a function of at least one system configuration including carrier type (eg, legacy carrier or other carrier type). In this case, if the same N _set number and CP length are used for the ePDCCH resource set, a larger number of available eCCEs can be specified in the non-legacy carrier type than in the case of legacy carriers, where the non-legacy carrier The type may mean that the carrier does not have legacy downlink control channels and CRSs of downlink subframes (eg, PDCCH, PHICH, and PCFICH).

A subset of an ePDCCH resource set or a configured ePDCCH resource set of multiple ePDCCH resource sets may be used for a WTRU or UE-specific search space. For example, if K _set =3 ePDCCH resource sets are defined, two ePDCCH resource sets (eg, sets 1 and 2) may be used as ePDCCH resources for a particular WTRU or UE. A plurality of ePDCCH resource sets may have at least one of the following attributes.

로서 규정될 수 있고, 여기에서 i=0,...,L-1, m'=m+M^(L)·n_CI, 및 m=0,...,M^(L)-1이다. Y_k는 Y_k = (A·Y_k-1)modD로 규정될 수 있고, 여기에서 Y_-1=n_RNTI≠0, A=39827, D=65537 및 k=└n_s/2┘이다.According to an exemplary embodiment, K _set ePDCCH resource sets are defined and each ePDCCH resource set may include an equal number of eCCEs (eg, 16 eCCEs). The number of eCCEs may be fixed or may vary according to system parameters. The eCCE index may be specified from 0 to the total number of eCCEs in a given number of ePDCCH resource sets. For example, if 3 ePDCCH resource sets are defined (eg, K _set =3) and each ePDCCH resource set includes 16 eCCEs, the eCCE index for the first ePDCCH resource set (eCCE#0, ..., eCCE#15), respectively (eCCE#16, ..., eCCE#31) and (eCCE#32, ..., eCCE#47) for the second and third ePDCCH resource sets. can be defined as The total number of eCCEs (N _eCCE ) may be K _set ·K _eCCE , where K _eCCE indicates the number of eCCEs in the ePDCCH resource set, and N _eCCE = K _set ·K _eCCE . The total number of eCCEs in subframe k may be denoted as N _eCCE,k . In one embodiment, the WTRU or UE-specific search space (S ^(L) _k ) is

, where i=0,...,L-1, m'=m+M ^(L) n _CI , and m=0,...,M ^(L) -1. Y _k can be defined as Y _k = (A·Y _k−1 )modD, where Y ₋₁ =n _RNTI ≠0, A=39827, D=65537 and k=└n _s /2┘.

An eCCE index may also be defined per ePDCCH resource set. For example, if three ePDCCH resource sets are defined (eg, K _set =3) and each ePDCCH resource set includes 16 eCCEs, the eCCE index is the first, second and/or third ePDCCH resource For a set, it can be specified as (eCCE#0, ..., eCCE#K _eCCE -1). A WTRU or UE-specific search space may be specified per ePDCCH resource set, where N _eCCE,k = K _eCCE,k . In this case, one or more of the following may apply. For example, a WTRU or UE specific search space may be defined per ePDCCH resource set. An ePDCCH candidate for an aggregation level may be divided into two or more ePDCCH resource sets. The ePDCCH resource set may be used for WTRU or UE specific search space. A subset of the ePDCCH resource set may be used for a specific WTRU or UE specific search space. In one embodiment, the subset may be different according to n _RNTI .

Table 14-4 shows an example where two sets of ePDCCH resources (e.g., n=0 and 1) are used for the WTRU or UE specific search space and the ePDCCH candidates are evenly partitioned into the two sets of ePDCCH resources.

[Table 14-4]

Aggregation level ePDCCH candidates

또는

로서 규정될 수 있다. Y_p,k는 ePDCCH 자원 집합마다 규정될 수 있고 동일한 서브프레임의 ePDCCH 자원 집합 인덱스(p)에 따라 다른 수를 가질 수 있다. A는 ePDCCH 자원 집합 인덱스에 따라 다른 수로 규정될 수 있다. 예시적인 실시형태에 있어서, Y_p,k는 n_RNTI, 서브프레임 번호, 및/또는 ePDCCH 자원 집합 인덱스(p)의 함수로서 규정될 수 있다. 추가로, Y_p,k는 Y_p,k = (A·Y_p,k-1)modD로 규정될 수 있고, 여기에서 Y_p,-1=n_RNTI≠0, D=65537 및 k=└n_s/2┘이다. A_p는 소수(prime number)로서 규정될 수 있고, A_p=0=39827일 때 0번째 집합이 제1 ePDCCH 자원 집합으로 될 수 있다. A_p,p>0은 39827보다 더 작거나 더 큰 소수일 수 있다. 예를 들면, A_p=0=39827 및 A_p=1=39829이다.The WTRU or UE-specific search space (S ^(L) _k,p ) for the set of ePDCCH resources (p) is

or

can be defined as Y _p,k may be defined for each ePDCCH resource set and may have a different number according to the ePDCCH resource set index p of the same subframe. A may be defined as a different number according to the ePDCCH resource set index. In an exemplary embodiment, Y _p,k may be defined as a function of n _RNTI , subframe number, and/or ePDCCH resource set index p. Additionally, Y _p,k can be defined as Y _p,k = (A Y _p,k-1 )modD, where Y _p,-1 =n _RNTI ≠0, D=65537 and k=└ n _s /2┘. A _p may be defined as a prime number, and when A _p=0 =39827, the 0th set may be the first ePDCCH resource set. A _p , p>0 can be a prime number smaller or larger than 39827. For example, A _p=0 =39827 and A _p=1 =39829.

Additionally, Y _p,k may be defined as Y _p,k = (A Y _p,k-1 + Δ _offset,p )modD, where Δ _offset,p is for the set of ePDCCH resources (p). is an offset In such an embodiment, Δ _offset,p may be defined as at least one of the following: upper layer composition value; A predefined number may be used for the ePDCCH resource set specific offset, for example Δ _{offset,p = 0} = 0 and Δ _{offset,p = 1} =λ, where λ is a predefined number (eg, 3) and/or the offset may be randomly generated (eg, Δ _offset,p=0 =0 and/or Δ _offset,p=1 =λ, where λ is the subframe number and /or may be generated as a function of WTRU or UE-ID (eg, C-RNTI)) and/or the offset may be specified as a function of one or more of the following: ePDCCH resource type (eg, C-RNTI) distributed or local), number of PRBs, level of aggregation, number of ePDCCH candidates, and/or number of eCCEs.

According to an exemplary embodiment, Y _p,k may also be defined as Y _p,k = (A _p Y _p,k-1 + Δ _offset,p )modD, where Δ _offset,p is the ePDCCH resource It is a set-specific offset.

A WTRU or UE-specific search space may be defined for multiple sets of ePDCCH resources and the location of ePDCCH candidates for blind detection may be defined as a function of the number of ePDCCH resource sets and the number of eCCEs.

Additionally, an eCCE index may be specified for each one or more ePDCCH resource sets, and the associated ePDCCH resource sets may be different depending on the ePDCCH transmission type and/or eCCE aggregation level. In this case, one or more of the following may apply. For example, an eCCE index may be defined per ePDCCH resource set in at least one of the following cases: A low eCCE aggregation level such as 1 and/or 2 may be used; and/or a set of ePDCCH resources may be configured as a distributed transmission. An eCCE index may be specified for two or more configured ePDCCH resource sets in at least one of the following cases: A high eCCE aggregation level, such as eg 8 or higher, may be used; and/or the set of ePDCCH resources may be configured as a localized transmission. One or more subsets of the ePDCCH resource set may be indicated from the indication channel (eg, enhanced PCFICH) of each subframe.

For multiple ePDCCH resource sets, each ePDCCH resource set may be independently configured as localized transmission or distributed transmission. If multiple ePDCCH resource sets are configured for a WTRU or UE, a subset of the configured ePDCCH resource sets may be configured for local transmission and the remaining ePDCCH resource sets may be configured for distributed transmission; ePDCCH candidates may be defined in different ways for local and distributed ePDCCH resource sets; Different hash functions may be used for local and distributed ePDCCH resource aggregation; and/or K _set ePDCCH resource sets may be defined and each ePDCCH resource set may have a different number of eCCEs (eg, 16 eCCEs for the primary set and 32 eCCEs for the secondary set).

When ePDCCH candidates are specified in different ways for local and distributed ePDCCH resource sets, one or more of the following may be applied and/or used: A hash function (Y _k ) is used for distributed ePDCCH resource sets. ; An offset value (K _offset ) is used for a set of local ePDCCH resources; An ePDCCH resource set dependent hash function may be used for a distributed ePDCCH resource set. When different hash functions are used for local and distributed ePDCCH resource sets, legacy hash functions are used for distributed ePDCCH resource sets and different hash functions can be defined for local ePDCCH resource sets.

Embodiments for antenna port mapping based on a search space may also be provided and/or used as described herein. For example, the same or similar ePDCCH candidates in a WTRU or UE-specific search space may have different antenna ports and/or scrambling IDs, and a common search space may have the same antenna ports and/or scrambling IDs. In such an embodiment, if the WTRU or UE specific search space is defined as {eCCE#n, ..., eCCE#n+k}, then the WTRU or UE behavior for monitoring the ePDCCH is one or more of the following can include Antenna ports for eCCEs within a WTRU or UE specific search space may be configured in a WTRU or UE specific manner. For example, one WTRU or UE may demodulate eCCE#n to antenna port-7 and another WTRU or UE may demodulate eCCE#n to antenna port-8. The antenna configuration may be informed to the WTRU or UE via higher layer signaling or implicitly derived from the RNTI. Antenna ports for eCCEs within the WTRU or UE-specific search space may be blind decoded within the WTRU or UE-specific search space. For example, a WTRU or UE specific search space may include eCCE#n with antenna port-7 and eCCE#n with antenna port-9. The WTRU or UE may also demodulate (eg, iteratively demodulate) the same resource (eCCE#n) to antenna port-7 and antenna port-9.

According to further embodiments, a DM-RS scrambling sequence may be provided and/or used. For example, for demodulation of ePDCCH, antenna ports {7, 8, 9, 10} may be used for channel estimation, and equivalently {107, 108, 109, 110} may be used. In this case, the DM-RS for the antenna port may be defined as follows.

Here, the sequence initialization c _init can be defined as follows.

와 (X_ID, n_SCID)는 상호 교환적으로 사용될 수 있다. c_init 정의에 대하여, 하기의 것 중 하나 이상을 적용할 수 있다: 상이한 스크램블링 시퀀스가 동일한 ePDCCH 자원에 대하여 사용되고 및/또는 단일 스크램블링 시퀀스가 셀 내의 ePDCCH 자원에 대하여 사용될 수 있다.From here

and (X _ID , n _SCID ) may be used interchangeably. For the c _init definition, one or more of the following may apply: different scrambling sequences may be used for the same ePDCCH resource and/or a single scrambling sequence may be used for the ePDCCH resource within a cell.

In an embodiment, different scrambling sequences may be used for the same ePDCCH resource (eg, PRB-pair) to increase multi-user multiplexing gain, for example depending on the WTRU or UE and/or blind decoding attempt. As an example, one WTRU or UE may demodulate eCCE#n into one scrambling sequence and another WTRU or UE may demodulate eCCE#n into another scrambling sequence, where the scrambling sequence is a demodulation reference signal (e.g. For example, it may be associated with an antenna port). As another example, the WTRU or UE may demodulate eCCE#n into scrambling sequences A and B. A scrambling sequence candidate can be defined as follows: a scrambling sequence candidate can be defined by n _SCID and/or X _ID ; A scrambling sequence candidate can be defined as {n _SCID =0, n _SCID =1}; and/or scrambling sequence candidates may be defined as {(X ₁ ,n _SCID =0, X ₂ ,n _SCID =0), (X ₁ ,n _SCID =1, X ₂ ,n _SCID =1)} where In , X ₁ and X ₂ may be different numbers defined in the range of 0 to 'number of cell IDs'.

A single scrambling sequence can also be used for ePDCCH resources within a cell, cell specific parameters can be used for X _IDs and a fixed number can be used for n _SCIDs . The X _ID can be defined as a physical cell ID or configured by higher layer signaling. n _SCID can be fixed as 0 or 1.

If multiple ePDCCH resource sets are specified, a scrambling sequence may be used per ePDCCH resource set or across ePDCCH resource sets. For example, a scrambling sequence may be defined per ePDCCH resource set. Additionally, X _IDs can be defined per ePDCCH resource set so that multiple scrambling sequences can be used without dynamic indication. In such an embodiment, when a set of ePDCCH resources is configured, an associated X _ID for each set of ePDCCH resources may also be configured. In this case, n _SCID can be fixed as 0 or 1. Two X _IDs are configured through the upper layer, and each ePDCCH resource set can use one of the X _IDs according to the configuration. A fixed predefined X _ID may be used for the ePDCCH candidates in the common search space so that the WTRU or UE can demodulate the ePDCCH candidates in the common search space. Higher-layer structured X _IDs may be used for ePDCCH candidates in the WTRU or UE-specific search space, and the X _IDs may vary from ePDCCH resource set to ePDCCH resource set or may be the same for an ePDCCH resource set. Two or more X _IDs may be used with multiple sets of ePDCCH resources, and the PDSCH associated with the ePDCCH may be received in a subframe in at least one of the following ways: A WTRU or UE may use the associated ePDCCH for PDSCH demodulation. You may use the same X _ID as used; and/or regardless of the X _ID used in the associated ePDCCH, the WTRU or UE may use the X _ID indicated by the n _SCID of the associated DCI. If n _SCID =0, X ₁ can be used. Otherwise, X ₂ may be used. If the WTRU or UE uses the same X _ID as used on the associated ePDCCH for PDSCH demodulation, a scrambling sequence is aligned between the PDSCH and the associated ePDCCH so that coordinated multipoint transmission (CoMP) operation can be applied on the ePDCCH.

The use of X _ID may depend on the configured transmission mode for PDSCH. For example, if the WTRU or UE is configured for non-CoMP operation, a single X _ID is used for the ePDCCH resource set, and the X _ID can be defined as the physical cell ID. However, if a WTRU or UE is configured for CoMP operation, more than one X _ID may be used, and each ePDCCH resource set may be independently configured with an X _ID . So, the X _IDs may or may not be identical for a set of ePDCCH resources.

로서 규정될 수 있고, 여기에서

는 ePDCCH 자원 집합마다 상위층을 통해 구성될 수 있고

는 고정 수(예를 들면, 0, 1 또는 2)일 수 있다. ePDCCH 공통 검색 공간의 경우에,

는 물리적 셀 ID의 함수로서 규정될 수 있고

는 고정 수(예를 들면, 0, 1 또는 2)일 수 있다. 예를 들면,

는 물리적 셀 ID이거나 물리적 셀 ID와 동일할 수 있다.In a further embodiment, the DM-RS sequence may be differently defined according to or based on the ePDCCH search space. For example, depending on the ePDCCH search space, one or more of the following may be applied and/or used and/or provided. In one embodiment, a WTRU or UE specific DM-RS sequence may be configured for a WTRU or UE specific search space and a cell specific DM-RS sequence may be used for a common search space. Sequence initialization (c _init ) for a WTRU or UE-specific search space

can be defined as, where

Can be configured through the upper layer for each ePDCCH resource set,

may be a fixed number (eg 0, 1 or 2). In the case of the ePDCCH common search space,

can be defined as a function of the physical cell ID and

may be a fixed number (eg 0, 1 or 2). For example,

may be a physical cell ID or the same as the physical cell ID.

In another embodiment, both the WTRU- or UE-specific search space and the common search space may consist of WTRU- or UE-specific DM-RS sequences or cell-specific DM-RS sequences.

로서 규정될 수 있고, 여기에서

는 ePDCCH 자원 집합마다 상위층을 통해 구성될 수 있고

는 고정 수(예를 들면, 0, 1 또는 2)일 수 있다.Additionally, in an embodiment, if multiple (eg, two) sets of ePDCCH resources are configured for an ePDCCH WTRU or UE-specific search space and (eg, one) set of ePDCCH resources are ePDCCH common When used for a set of resources, one or more of the following may be applied and/or used and/or provided. For example, sequence initialization (c _init ) for a WTRU or UE-specific search space may be performed for each set of ePDCCH resources if the ePDCCH WTRU or UE-specific resources do not overlap with the ePDCCH common search space resources. method can be specified. In such an embodiment, the sequence initialization (c _init ) for the WTRU or UE-specific search space is

can be defined as, where

Can be configured through the upper layer for each ePDCCH resource set,

may be a fixed number (eg 0, 1 or 2).

로서 규정될 수 있고, 여기에서

는 ePDCCH 자원 집합마다 상위층을 통해 구성될 수 있고

는 고정 수(예를 들면, 0, 1 또는 2)일 수 있다.For a set of ePDCCH WTRU or UE-specific search space resources that overlap in whole and/or part with ePDCCH common search space resources, the sequence initialization (c _init ) for the WTRU or UE-specific search space is the ePDCCH common search space DM-RS It can be defined the same as sequence initialization. In such an embodiment, if the ePDCCH common search uses a cell-specific DM-RS sequence, the WTRU or UE-specific DM-RS sequence for the set of ePDCCH resources overlapping the common search space is the cell-specific DM-RS sequence. can be used. Additionally, in such an embodiment, the sequence initialization (c _init ) for the WTRU or UE-specific search space is such that, if the WTRU or UE-specific search space does not overlap with the ePDCCH common search space,

can be defined as, where

Can be configured through the upper layer for each ePDCCH resource set,

may be a fixed number (eg 0, 1 or 2).

로서 규정될 수 있고, 여기에서

는 물리적 셀 ID의 함수로서 구성될 수 있고

는 고정 수(예를 들면, 0, 1 또는 2)일 수 있다. 예를 들면,

는 물리적 셀 ID이거나 물리적 셀 ID와 동일할 수 있다.Additionally, in an exemplary embodiment, the sequence initialization (c _init ) for the WTRU or UE specific search space is such that if the WTRU or UE specific search space overlaps with the ePDCCH common search space:

can be defined as, where

can be configured as a function of the physical cell ID and

may be a fixed number (eg 0, 1 or 2). For example,

may be a physical cell ID or the same as the physical cell ID.

A search space scheme (eg, in CA or across multiple DL carriers) may be provided as described herein. For example, a search space associated with a plurality of DL carriers may be implemented. For ePDCCH resources, a common search space and a WTRU or UE specific search space may be defined. A search space may be defined in a multi-carrier system in one or more of the following ways.

A common search space may be limited to being defined in PCells and/or a WTRU or UE specific search space may be defined in multiple component carriers. A WTRU or UE may restrict monitoring of a common search space for a PCell and a WTRU or UE-specific search space of a corresponding PCell/SCell. In the common search space, a carrier indication field (CIF) may indicate a corresponding component carrier in DCI format. The component carrier on which the ePDCCH is received in the WTRU or UE-specific search space can be thought of as the corresponding component carrier. 26 shows an exemplary common search space definition that may be limited to, for example, the legacy PDCCH region of a PCell. The WTRU or UE specific search space and common search space that can be defined in the PCell can be defined with multiple component carriers.

A common search space may also be defined in the Pcell and a WTRU or UE specific search space may be defined in the at least one Scell. A common search space may be defined in the legacy PDCCH of the PCell and/or a WTRU or UE specific search space may be defined in the ePDCCH of the at least one SCell.

In an embodiment, a PCell may be independently defined for legacy PDCCH and/or ePDCCH. In this case, if there are Cell-0, Cell-1 and Cell-2, Cell-0 may be configured as a PCell for legacy PDCCH and/or Cell-2 may be configured as a PCell for ePDCCH. The PCell for the ePDCCH may be defined along with an offset for the PCell of the legacy PDCCH.

Both the WTRU or UE specific search space and the common search space may be constrained to be defined in the Pcell. Additionally, both the WTRU or UE specific search space and the common search space may be defined with multiple component carriers.

According to an exemplary embodiment, two ePDCCH modes are defined and/or eg ePDCCH frequency diversity mode (eg ePDCCH mode-1) and ePDCCH frequency selectivity mode (eg ePDCCH mode-2). can be used Additionally, ePDCCH mode-1 can achieve frequency diversity gain such that the common search space is limited to what is defined by ePDCCH mode-1.

In an embodiment, a WTRU or UE specific search space may be defined in one or more of the following ways. A WTRU or UE specific search space may be defined by ePDCCH mode-1 or ePDCCH mode-2. The ePDCCH mode of a WTRU or UE specific search space may be configured by RRC signaling such that the WTRU or UE limits its monitoring to ePDCCH mode-1 or ePDCCH mode-2 depending on its configuration. Additionally, the ePDCCH mode of the WTRU or UE specific search space may be configured according to the SFN such that the WTRU or UE knows from its SFN number which ePDCCH modes may be specified in a subframe. In another exemplary embodiment, the ePDCCH mode of a WTRU or UE specific search space may be configured according to the component carrier. For example, ePDCCH mode-1 may be configured in the PCell and ePDCCH mode-2 may be configured for the secondary cell (SCell). The WTRU or UE may monitor ePDCCH of PCell along with ePDCCH mode-1 and ePDCCH mode-2 of SCell. The ePDCCH mode of each component carrier may be configured by higher layer signaling.

Also, ePDCCH mode-1 and ePDCCH mode-2 may be defined in the same subframe. In the case of blind decoding, the WTRU or UE may decode one half in ePDCCH mode-1 and the other half in ePDCCH mode-2. The portion of the ePDCCH mode that the WTRU or UE blind decodes may vary from subframe to subframe and/or may be configured by the eNB. Table 15 shows an example in which M ^(L) ₁ and M ^(L) ₂ indicate the number of ePDCCH candidates for ePDCCH mode-1 and mode-2, respectively. A WTRU or UE may monitor one ePDCCH mode configured by the eNB via higher layer signaling.

ePDCCH candidates monitored by WTRU or UE Search space (S ^(L) _k ) Number of ePDCCH candidates category Aggregation level (L) size (number of CCEs) M ^(L) ₁ M ^(L) ₂
WTRU or UE specific One 6 3 3 2 12 3 3 4 8 One One 8 16 One One common type 4 16 4 8 16 2

If cross-carrier scheduling is active, the PDCCH can be limited to transmitting on the PCell, so the WTRU or UE can monitor the PCell on limited occasions receiving the PDCCH. When ePDCCH is specified, WTRU or UE behavior may be specified in one or more of the following ways when cross-carrier scheduling is activated. Legacy PDCCH and/or ePDCCH may be limited to being transmitted in the Pcell according to the PDCCH configuration. If the eNB configures the legacy PDCCH for the WTRU or UE, the WTRU or UE may be limited to monitoring the legacy PDCCH in the PCell. Otherwise, the WTRU or UE may monitor the ePDCCH in the PCell. The WTRU or UE may assume that each PDCCH is transmitted on the PCell. In addition, the PCell may be independently defined for legacy PDCCH and ePDCCH, such as PCell_pdcch and PCell_epdcch, where PCell_pdcch and PCell_epdcch are respectively Pcell for legacy PDCCH and ePDCCH is indicated. A WTRU or UE may monitor PCell_epdcch for a set of component carriers configured for ePDCCH and PCell_pdcch for other component carriers configured for legacy PDCCH. PCell_pdcch and PCell_epdcch may be the same component carrier.

Interference randomization may also be provided and/or used as described herein. For example, the frequency location of an ePDCCH may be changed from one subframe to another subframe to randomize interference between ePDCCHs from a plurality of cells.

For such interference randomization, the WTRU or UE may use various behaviors. For example, the behavior of a WTRU or UE monitoring ePDCCH can be specified as follows. If cross-carrier scheduling is active, the WTRU or UE monitors the ePDCCH on a specific cell within a subframe and the index specific cell may be implicitly derived from the SFN number and/or radio frame. If cross-carrier scheduling is not active, the WTRU or UE can monitor the ePDCCH on each configured component carrier, but the ePDCCH resource changes from one subframe to another within the cell depending on the number of SFNs and/or radio frames. It can be.

Depending on the exemplary embodiment, WTRU or UE receiver processing may be used and/or provided. For example, PDSCH decoding processing time relaxation may be provided. In such embodiments, FDD (eg, with frame structure 1) and/or TDD (eg, with frame structure 2) may be provided and/or used. For example, TBS can be defined by (I _TBS , N _PRB ) (eg as shown in Section 7.1.7.2.1 “Physical Layer Procedures”, V10.1.0, 2011-03 of 3GPP TS 36.213) , the transport block size can increase as the number of (I _TBS , N _PRB ) increases, where 0≤I _TBS ≤26 and 1≤N _PRB ≤110. Since the ePDCCH can be transmitted in the PDSCH region, the WTRU or UE receiver, when receiving the PDSCH in downlink subframe n, reduces the decoding processing time of the HARQ-ACK transmission that can be used to be transmitted in uplink subframe n+4. can lose Timing advance (T _TA ) can reduce the PDSCH decoding process because the uplink signal T _TA is transmitted first, where 0≤T _TA ≤0.67 [ms]. Since a larger transport block size uses more PDSCH processing time, a larger TBS may be limited when the T _TA value is relatively large and ePDCCH is used. TBS restrictions may be used according to one or more of the following.

In an exemplary method, the TBS limit may be used as follows (eg, in accordance with one or more of the following). For example, if I ^Max _TBS ≤ I _TBS and N ^Max _PRB ≤ N _PRB , then I ^Max _TBS and N ^Max _PRB can be specified, where I ^Max _TBS and N ^Max _PRB are the maximum number of TBS indexes and PRBs to be limited. represents the number of So, the WTRU or UE may assume that no TBS greater than (I ^Max _TBS , N ^Max _PRB ) is transmitted for the WTRU or UE. I ^Max _TBS and N ^Max _PRB may be specified in a WTRU or UE specific manner as a function of a WTRU or UE specific timing advance value (T _TA ). Max TBS(N ^Max _TBS ) can also be expressed as N ^Max _TBS = Δ(I ^Max _TBS , N ^Max _PRB ), where Δ can be the TBS table.

Additionally, I ^Max _TBS , N ^Max _PRB can be defined as a function of the timing advance value by at least one of the following equations: I ^Max _TBS = └I _TBS ×(1-γ·T _TA )┘ or ┌I _TBS ×(1-γ·T _TA )┐ (where γ is a weighting factor); and/or N ^Max _PRB =└N _PRB ×(1-δ·T _TA )┘ or ┌N _PRB ×(1-δ·T _TA )┐, where δ is a weighting factor.

I ^Max _TBS , N ^Max _PRB may also be defined as a function of the timing advance value by at least one of the following equations: I ^Max _TBS = I _TBS -└γ·T _TA )┘ or I _TBS -┌γ·T _TA )┐ (where γ is a weighting factor); and/or N ^Max _PRB = N _PRB -└δ T _TA )┘ or N _PRB -┌δ T _TA )┐, where δ is the weighting factor.

In an embodiment, N ^Max _TBS may be defined as a function of the timing advance value by at least one of the following equations: N ^Max _TBS = └N _TBS x (1-ε T _TA )┘ or ┌N _TBS x ( 1-ε·T _TA )┐, where N _TBS represents the unrestricted maximum TBS size and ε is the weighting factor; and/or N ^Max _TBS = N _TBS -└ε T _TA )┘ or N _TBS -┌ε T _TA )┐.

The weighting factors (γ, δ, ε) used as described above may have the following properties: the weighting factors may vary depending on the WTRU or UE class/category and/or the weighting factors may vary depending on the transmission mode. It can be. Additionally, Max TBS N ^Max _TBS may be specified as a function of T _TA and WTRU or UE class/category. For example, in the case of a WTRU or UE category-1, the TBS limit may not be used regardless of the timing advance value.

In another example method, H-ARQ timing can be implemented (eg, to allow for additional decoding processing time). For H-ARQ operation, a WTRU or UE may be requested to transmit a HARQ-ACK in subframe n+k if the WTRU or UE received a PDSCH in subframe n. In such an embodiment, k is set to 4 in the FDD system and k may be predefined in the TDD system, for example based on UL-DL configuration and/or subframe number. Additionally, in such an embodiment, the WTRU or UE behavior may be specified as follows (eg, when the WTRU or UE receives the ePDCCH and corresponding PDSCH in subframe n). A WTRU or UE may transmit HARQ-ACK in subframe n+l. In such an embodiment, the variable l may be set to k if a single component carrier is active. Additionally, the variable l may be set to a positive integer greater than 4 if multiple component carriers are active. The variable l may also consist of a number in the candidate set, for example {4, 6, 8, 10}, via higher layer signaling when multiple component carriers are activated. If a single component carrier is active, l may be set to k.

In a further exemplary method, the ePDCCH and corresponding PDSCH may be transmitted in different subframes such that the WTRU or UE monitors the ePDCCH in subframe n-i and expects to receive the corresponding PDSCH in subframe n. In this case, the WTRU or UE behavior for HARQ-ACK transmission may include one or more of the following.

For example, the variable i may be '0' or a positive integer, and may be configured by higher layer signaling. In one embodiment, variable i may be set to '1' in the FDD system. A WTRU or UE may transmit HARQ-ACK in subframe n-k regardless of the subframe number for ePDCCH reception. The ePDCCH may be limited to transmission in subframe n-i when a plurality of component carriers are activated. Otherwise, ePDCCH and corresponding PDSCH may be transmitted in the same subframe.

The ePDCCH may also be transmitted in subframe ni if the timing advance (T _TA ) for the WTRU or UE is greater than the threshold α. If T _TA >α, the WTRU or UE can expect to receive the corresponding PDSCH in subframe n when the WTRU or UE receives the ePDCCH in subframe ni. If T _TA ≤ α, then the WTRU or UE may receive (eg, expect to receive) the ePDCCH and the corresponding PDSCH in the same subframe (eg, α=0.17 ms).

Additionally, the ePDCCH may be transmitted in subframe ni if the number of available downlink PRBs (eg, related to system bandwidth) is greater than N _PRBs . N _PRB is the threshold, and in an exemplary embodiment N _PRB =50. The ePDCCH may also be transmitted in subframe ni for Category 5 UEs.

Combinations of one or more of the foregoing embodiments may also be implemented. For example, ePDCCH may be transmitted in subframe ni if multiple component carriers are active and the timing advance (T _TA ) for the WTRU or UE is greater than a threshold. The ePDCCH may be transmitted in subframe ni if the timing advance (T _TA ) for the WTRU or UE is greater than the threshold and the WTRU or UE category is 5. The ePDCCH may be transmitted in subframe ni if the timing advance (T _TA ) for the WTRU or UE is greater than the threshold and the number of available downlink PRBs (eg, system bandwidth) is greater than N _PRBs .

TDD (eg Frame Structure 2) implementations may also be provided and/or used as described herein. For example, in TDD, the HARQ-ACK timing depends on the UL-DL configuration and/or subframe because the uplink subframe is unavailable at n+4, for example when the WTRU or UE receives the PDSCH in subframe n. It can be defined according to or based on the number. Table 16 shows an exemplary embodiment of the HARQ-ACK timing relationship according to specifying k such that the WTRU or UE transmits HARQ-ACK in uplink subframe n+k when detecting a PDSCH in downlink subframe n .

k for TDD configurations 0-6 TDD UL-DL configuration subframe n
A WTRU or UE may transmit a HARQ-ACK response in UL subframe n+k when detecting PDSCH in downlink subframe n 0 One 2 3 4 5 6 7 8 9 0 4 6 U U U 4 6 U U U One 7 6 U U 4 7 6 U U 4 2 7 6 U 4 8 7 6 U 4 8 3 4 11 U U U 7 6 6 5 5 4 12 11 U U 8 7 7 6 5 4 5 12 11 U 9 8 7 6 5 4 13 6 7 7 U U U 7 7 U U 5

In an embodiment, the TBS limit may be applied to subframes with k less than or equal to K, where the value of K may be predefined or configured by higher layer signaling. As an example, if K is equal to 4, the TBS restriction may be applied to subframes 0 and 5 of UL-DL configuration 0 of Table 16 and may be applied to subframe 4 of UL-DL configuration 1. As another example, if K is equal to 5, the TBS restriction may be applied in one or more of the following subframes: subframe {0, 5} of configuration 0; Subframe {4, 9} of configuration 1; Subframe {3, 8} of configuration 2; subframe {0} of configuration 3; Subframe {8, 9} of configuration 4; Subframe {7, 8} of configuration 5; and subframe {9} of configuration 6. According to a further embodiment, the TBS restriction may be applied to subframes where the HARQ-ACK timing is greater than K and the WTRU or UE has T _TA >α. Also, from the perspective of the WTRU or UE PDSCH decoding procedure, the WTRU or UE may infer that the maximum TBS limit does not apply if the HARQ-ACK timing (k) is greater than K (eg, 4) in the subframe. . So, other WTRU or UE behaviors may be specified. For example, if the WTRU or UE receives a TBS within the limited TBS of a subframe when the HARQ-ACK timing (k) is equal to or less than K, the WTRU or UE reports that such reception is erroneous and in subframe n+k It can be assumed to report DTX or NACK. If the WTRU or UE receives a TBS within the limited TBS of a subframe when the HARQ-ACK timing (k) is greater than K, the WTRU or UE may start decoding the PDSCH and report the HARQ-ACK in subframe n+k. can In case of TDD and FDD, the TBS restriction may apply in the downlink subframe if the WTRU or UE reports HARQ-ACK 4 ms after PDSCH reception in the subframe.

Embodiments for feedback processing time reduction (eg, using FDD (eg, frame structure 1) and TDD (eg, frame structure 2)) are described herein. As discussed above, aperiodic CSI feedback may be provided and/or used. If aperiodic CSI reporting is triggered in downlink subframe n, the WTRU or UE may report CSI in uplink subframe n+4. Since CSI calculation uses additional processing time, when aperiodic CSI reporting is triggered by ePDCCH in downlink subframe n, the WTRU or UE behavior may include at least one of the following.

The WTRU or UE may drop CSI feedback if the PDSCH is transmitted for the WTRU or UE in the same subframe. In this case, the suspension condition may be further constrained by at least one of the following: TBS for PDSCH in subframe n greater than a predefined threshold; aperiodic CSI feedback mode using subband CQI and/or class; a timing advance greater than a predefined threshold (T _TA ); CSI-RS associated with aperiodic CSI feedback transmitted in the same subframe; System bandwidth (N _PRB ) greater than a predefined threshold (eg 50), etc.

In an embodiment, the WTRU or UE may not assume that the aperiodic CSI report is triggered in subframe n over the ePDCCH if the PDSCH is transmitted in the same subframe. Such conditions may be further constrained by at least one of the following: TBS for PDSCH in subframe n greater than a predefined threshold; aperiodic CSI feedback mode using subband CQI and/or class; a timing advance greater than a predefined threshold (T _TA ); CSI-RS associated with aperiodic CSI feedback transmitted in the same subframe; System bandwidth (N _PRB ) greater than a predefined threshold (eg 50), etc.

Additionally, if the CSI request field in DCI formats 0 and 4 triggers an aperiodic CSI report in subframe n, the WTRU or UE may feedback the CSI in subframe n+4 in the FDD system. In an embodiment, this WTRU or UE behavior may be provided if the WTRU or UE receives a legacy PDCCH.

According to an exemplary embodiment, if a WTRU or UE receives an ePDCCH for aperiodic CSI reporting in a multi-carrier system, the WTRU or UE behavior may include one or more of the following. A WTRU or UE may report CSI feedback in subframe n+j, where j may be set to 4 if a single component carrier is active; j may be set to 5 regardless of the number of configured component carriers (cells); j may be used when a plurality of component carriers are configured by higher layers; j may be defined according to the cell such that j is set to 4 for PCell and 5 for Scell and the reporting times for PCell and Scell are separated in the time domain; and/or j may be set to a number greater than 4 when the WTRU or UE is configured according to at least one of the following; A timing advance (T _TA ) for a WTRU or UE greater than the threshold, an aperiodic reporting triggering bit indicating to report CSI for multiple component carriers, and/or a configured PUSCH reporting mode indicating a subband precoding matrix indicator ( PMI) if based on reporting.

Thus, WTRU or UE processing (eg, WTRU or UE decoding processing) time relief in multiple carriers may be provided as described herein. In such an embodiment, the timing relationship and/or aperiodic CSI feedback for HARQ-ACK transmission may be redefined when the ePDCCH is used in a multi-carrier system, for example. Additionally, PDSCH decoding processing may be provided.

Uplink control channel assignment by ePDCCH is also described herein. For example, PUCCH resource mapping for a single DL carrier may be provided. In such embodiments, PUCCH resources corresponding to DL designation messages received on ePDCCH may be configured as a function of RRC signaling indicated for one or more WTRUs or UEs.

When ePDCCH reception is enabled or configured for a WTRU or UE, at least one candidate PUCCH resource or set of candidate PUCCH resources may be designated or indicated for the WTRU or UE. PUCCH resources may be indicated or signaled to one or more WTRUs or UEs using per-WTRU-specific signaling or per-UE-specific signaling, or PUCCH resources may be indicated or signaled to WTRUs or UEs in a cell-specific manner. . The WTRU or UE may determine the corresponding PUCCH resource of the UL subframe as a function of the allowed or pre-configured PUCCH resource after receiving the DL designation message on the ePDCCH of the DL subframe.

In another embodiment, the designated ePDCCH resource may correspond to a predetermined or configured set of PUCCH resources. A WTRU or UE receiving a designation of an ePDCCH resource for decoding DL control information may obtain the corresponding PUCCH resource or set of allowable PUCCH resources as a function or table of predetermined mapping relationships. For example, the WTRU or UE may transmit PUCCH resources on a single designated PUCCH resource, or if more than one PUCCH resource is configured, designated or indicated, the WTRU or UE may transmit PUCCH on a selected resource from the set. In this case, the determination of a specific PUCCH resource is derived as a function of parameters such as the signaled value part of the DCI (eg, ARI of the TPC field of Release 10), or transmission configuration such as mapping of DL specific messages to ePDCCH resources. It may take at least 1 second to determine one or more values (eg, values related to antenna port numbers for DMRS of MU-MIMO). For a small number or requisite-size number of WTRUs or UEs decoding ePDCCH, the explicit configuration of corresponding PUCCH resources may be under the control of the network, avoiding the introduction of protocols dealing with legacy WTRUs decoding PDCCH Flexibility may be provided in aggregating PUCCH resources.

Additionally, PUCCH resources corresponding to DL designation messages received on ePDCCH may be derived through dynamic resource allocation mechanism techniques as a function of one or more transmission configurations of at least one DL signal received on ePDCCH. A PUCCH resource derived using a CCE index (n _CCE ) in PDCCH may be extended by defining the number of CCEs for ePDCCH transmission. In such embodiments, PUCCH resource collisions between legacy PDCCH and ePDCCH can be avoided while reusing similar PUCCH resource allocation principles, such as when legacy WTRUs or UEs and ePDCCH WTRUs or UEs are supported in the serving cell.

로서 규정 또는 도출될 수 있고, 안테나 포트 1에 대한 PUCCH 자원은

에 의해 도출될 수 있다. 여기에서, n_CCE는 ePDCCH의 영역에서 대응하는 PDCCH의 송신을 위해 사용된 제1 CCE의 수(예를 들면, 최저 eCCE 인덱스)이고, N^PDCCH _CCE는 레가시 PDCCH에 대한 제어 영역 내의 CCE의 총 수이며, N⁽¹⁾ _PUCCH는 상위층에 의해 구성될 수 있다. 이 경우에, 하기의 것 중 하나 이상이 적용될 수 있다. N^PDCCH _CCE는 PCFICH의 검출(예를 들면, OFDM 심벌의 수의 검출) 및 시스템 대역폭에 기초하여 동적으로 계산될 수 있다. N^PDCCH _CCE는 미리 규정된 오프셋 값, 예를 들면 최대 시스템 대역폭의 최대 CCE 수로 설정될 수 있고, 상위층에 의해 N⁽¹⁾ _ePUCCH = N⁽¹⁾ _PUCCH + N^PDCCH _CCE를 구성하도록 N⁽¹⁾ _PUCCH와 결합될 수 있다. N⁽¹⁾ _ePUCCH = N⁽¹⁾ _PUCCH + N^PDCCH _CCE는 자원 할당이 n^(1,p0) _PUCCH = n_eCCE + N⁽¹⁾ _ePUCCH 및 n^(1,p1) _PUCCH = n_eCCE + N⁽¹⁾ _ePUCCH + 1에 기초를 두도록 상위층 시그널링에 의해 구성될 수 있다. 이 경우에, 하기의 것 중 적어도 하나가 적용될 수 있다: N⁽¹⁾ _PUCCH는 상위층에 의해 구성되고 및/또는 PDCCH 및 ePDCCH에 대하여 공동으로 사용될 수 있고(예를 들면, 이 경우에 N^PDCCH _CCE는 상위층에 의해 구성됨); 및/또는 N⁽¹⁾ _ePUCCH는 N^PDCCH _CCE의 별도의 표시 없이 상위층 시그널링에 의해 구성될 수 있다.PUCCH resource allocation by a single set of ePDCCH resources may also be provided and/or used. For example, PUCCH resources for a single ePDCCH set may be defined as described herein. In one embodiment, if the eCCE and/or eREG units of ePDCCH are defined similarly to legacy PDCCH, then the corresponding PUCCH resource is for antenna port 0

Can be defined or derived as , and the PUCCH resource for antenna port 1 is

can be derived by Here, n _CCE is the number of first CCEs used for transmission of the corresponding PDCCH in the ePDCCH region (eg, the lowest eCCE index), and N ^PDCCH _CCE is the total number of CCEs in the control region for the legacy PDCCH. , and N ⁽¹⁾ _PUCCHs can be configured by higher layers. In this case, one or more of the following may apply. N ^PDCCH _CCEs may be dynamically calculated based on detection of the PCFICH (eg, detection of the number of OFDM symbols) and system bandwidth. N ^PDCCH _CCE may be set to a predefined offset value, for example, the maximum number of CCEs of the maximum system bandwidth, and configured by higher layers to N ⁽¹⁾ _ePUCCH = N ⁽¹⁾ _PUCCH + N ^PDCCH _CCE N ⁽¹⁾ It can be combined with _PUCCH . N ⁽¹⁾ _ePUCCH = N ⁽¹⁾ _PUCCH + N ^PDCCH _CCE means that the resource allocation is n ^(1,p0) _PUCCH = n _eCCE + N ⁽¹⁾ _ePUCCH and n ^(1,p1) _PUCCH = n _eCCE + N ^{(1 )} can be configured by higher layer signaling to be based on _ePUCCH + 1. In this case, at least one of the following may apply: N ⁽¹⁾ _PUCCH may be configured by higher layers and/or used jointly for PDCCH and ePDCCH (e.g., N ^PDCCH _CCE in this case) is constituted by the upper layer); And/or N ⁽¹⁾ _ePUCCHs may be configured by higher layer signaling without separate indication of N ^PDCCH _CCEs .

Additionally, in one embodiment, PUCCH resources are independent of n _eCCE such that n ^(1,p0) _PUCCH = N ⁽¹⁾ _ePUCCH , and N ⁽¹⁾ _ePUCCH can be configured by higher layers. For a transmission mode supporting one or more (eg, up to two) antenna ports, n ^(1,p1) _PUCCH may be given by n ^(1,p1) _PUCCH = N ⁽¹⁾ _ePUCCH + 1 . If the WTRU or UE is configured for MU-MIMO transmission, another decision parameter (n _MU ) may be used for the corresponding PUCCH resource in addition to n _eCCE , for example: n ^(1,p0 for antenna port 0) ⁾ _PUCCH = n _eCCE + N ^PDCCH _CCE + N ⁽¹⁾ _ePUCCH + n _MU and n ^(1,p1) _PUCCH = n _eCCE + N ^PDCCH _CCE + 1 + N ⁽¹⁾ _ePUCCH + n _MU for antenna port 1. In such an embodiment, n _MU may be determined as at least one of the following: a parameter associated with an antenna port for UE-specific DMRS; parameters similar to ARI (ACK/NACK Resource Indicator) configured by higher layer signaling; and/or predetermined parameters.

As another example, a PUCCH resource corresponding to a DL designation received on ePDCCH may be derived as a function of the number of CCEs. For example, an initial or predetermined CCE or equivalent mapping unit in an ordered sequence may be obtained from decoding of a DL specific message that may be mapped to a time and/or frequency resource grid.

Additionally, the sequence of mapping units such as eCCEs or eREGs selected to dynamically derive or determine PUCCH resource selection in a WTRU or UE decoding the ePDCCH is a CCE sequence used in conjunction with the dynamic PUCCH resource allocation used when decoding the PDCCH. and may or may not have a predetermined relationship with the starting CCE index. The WTRU or UE decoding the ePDCCH determining its PUCCH resource determines the UL transmission configuration from an initial dynamically calculated transmission configuration such as a starting (e)CCE or equivalent and one or more preconfigured or signaled parameters as described herein. can be calculated.

According to an exemplary embodiment, PUCCH resources that may be used with PDCCH (if any) and ePDCCH may be split or aggregated for WTRUs designated by the network to decode either of them. Upon setup, PUCCH resources may aggregate UL RBs, for example, for decoding of legacy WTRUs or UEs of PDCCH and decoding of WTRUs or UEs of ePDCCH. In some additional embodiments (eg, when trying to achieve spatial multiplexing gains), a separate UL resource may be selected for WTRU decoding of legacy PDCCH as opposed to decoding ePDCCH.

In the above example, when introducing the (e)CCE and/or (e)REG unit, the group or unit of REs is the same as the REG including 4 REs used in CCE or PDCCH where they contain 9 REGs. It may or may not be implied that it is. Additionally, the ordered sequence of mapping units corresponding to time and/or frequency resource allocation for one or more ePDCCHs may be the same in the embodiments described herein. In an embodiment, PUCCH resources for WTRU or UE decoding of at least one ePDCCH, which may be configured to receive two or more DL serving cells, may be derived via RRC signaling to one or more WTRUs or UEs.

로서 도출되고, 및/또는 안테나 포트 p1에 대한 PUCCH 자원은

에 의해 도출될 수 있다. 여기에서 n_eCCE는 UE용으로 구성된 ePDCCH 집합의 영역에서 대응 PDCCH의 송신을 위해 사용될 수 있는 제1 eCCE의 수(예를 들면, PDCCH를 구성하기 위해 사용될 수 있는 최저 eCCE 인덱스)이고,

는 ePDCCH 집합의 PUCCH 자원 오프셋이며, N⁽¹⁾ _PUCCH는 상위층에 의해 구성될 수 있다. 이 실시형태에 있어서, 하기의 것 중 하나 이상을 적용할 수 있다:

는 PCFICH의 검출(예를 들면, OFDM 심벌의 수의 검출) 및 시스템 대역폭에 기초하여 동적으로 계산될 수 있고;

는 미리 규정된 오프셋 값, 예를 들면 최대 시스템 대역폭의 최대 CCE 수로 설정되고 및/또는

가 상위층에 의해 구성되도록 N⁽¹⁾ _PUCCH와 결합될 수 있으며; 및/또는 상위층 시그널링에 의해

이 구성되어, 결과적인 자원 할당이

및

에 기초를 둘 수 있다. 상기 최종의 실시형태에 있어서, 하기의 것 중 적어도 하나가 적용될 수 있다: N⁽¹⁾ _PUCCH는 상위층에 의해 구성되고 및/또는 PDCCH 및 ePDCCH에 대하여 사용될 수 있다(예를 들면, 이 경우에

는 상위층에 의해 구성될 수 있다); N⁽¹⁾ _ePUCCH는 N^PDCCH _CCE의 별도의 표시 없이 상위층 시그널링에 의해 구성될 수 있다; 및/또는 N⁽¹⁾ _ePUCCH는 집합마다 독립적으로 구성될 수 있고, 이것은

로서 규정될 수 있다.Embodiments for PUCCH resource allocation by multiple sets of ePDCCH resources are also described herein. For example, if an eCCE or eREG of an ePDCCH set is defined similarly to a legacy PDCCH, then the corresponding PUCCH resource for the UE is for antenna port p0.

Is derived as, and / or the PUCCH resource for antenna port p1 is

can be derived by Here, n _eCCE is the number of first eCCEs that can be used for transmission of the corresponding PDCCH in the region of the ePDCCH set configured for the UE (eg, the lowest eCCE index that can be used to configure the PDCCH),

is the PUCCH resource offset of the ePDCCH set, and N ⁽¹⁾ _PUCCHs may be configured by higher layers. In this embodiment, one or more of the following may apply:

may be dynamically calculated based on the detection of the PCFICH (eg, detection of the number of OFDM symbols) and the system bandwidth;

Is set to a predefined offset value, for example, the maximum number of CCEs of the maximum system bandwidth, and/or

may be combined with N ⁽¹⁾ _PUCCHs so that is configured by higher layers; and/or by higher layer signaling

is constructed, the resulting resource allocation is

and

can be based on In the above final embodiment, at least one of the following may be applied: N ⁽¹⁾ _PUCCH may be configured by higher layers and/or used for PDCCH and ePDCCH (e.g., in this case

may be constituted by an upper layer); N ⁽¹⁾ _ePUCCHs can be configured by higher layer signaling without separate indication of N ^PDCCH _CCEs ; and/or N ⁽¹⁾ _ePUCCHs may be independently configured for each set, which

can be defined as

N ^(1),k _ePUCCHs (where k=0,1,...,K-1) may also be configured and/or indicated via dynamic signaling. For example, PUCCH resource allocation based on ePDCCH can be defined as n ^(1,p0) _PUCCH = n _eCCE + N ^(1),k _ePUCCH . In this case, one or more of the following may apply. k may be dynamically indicated by the DCI associated with the PDSCH transmission of the subframe. For example, the bit field may indicate the value of k so that the UE can derive PUCCH resources. Additionally, the DCI's ARI can be reused to indicate k. K may be equal to the number of configured ePDCCH resource sets and/or each k may be 1:1 mapped with the configured ePDCCH resource set. K can also be defined as 2 or 4, and/or K=1 when a single set of ePDCCH resources is configured.

은 N⁽¹⁾ _PUCCH와 결합될 수 있고, 여기에서 예를 들면

이고, N⁽¹⁾ _ePUCCH는 동적으로 신호될 수 있고 및/또는 반정적으로 또는 상위층에 의해 구성될 수 있다. 만일 WTRU 또는 UE가 MU-MIMO 송신과 함께 구성되면, 다른(예를 들면, 제2) 결정 파라미터(n_MU)가 다음과 같이 n_eCCE에 추가하여 대응하는 PUCCH 자원에 대해 사용될 수 있다: 안테나 포트 p0에 대하여

및 안테나 포트 p1에 대하여

이고, 여기에서 n_MU는 하기의 것 중 적어도 하나로서 결정될 수 있다: UE 특유형 DMRS에 대한 안테나 포트와 연합되는 파라미터; 상위층 시그널링에 의해 구성된 ARI와 유사한 파라미터; 및/또는 미리 정해진 파라미터.In an alternative or additional embodiment,

Can be combined with N ⁽¹⁾ _PUCCH , where for example

, N ⁽¹⁾ _ePUCCHs can be dynamically signaled and/or semi-statically or configured by higher layers. If the WTRU or UE is configured with MU-MIMO transmissions, another (eg, second) decision parameter (n _MU ) may be used for the corresponding PUCCH resource in addition to n _eCCE as follows: antenna port About p0

and for antenna port p1

, where n _MU may be determined as at least one of: a parameter associated with an antenna port for UE-specific DMRS; parameters similar to ARI configured by higher layer signaling; and/or predetermined parameters.

PUCCH resource mapping to multiple DL carriers may also be provided and/or used as described herein. For example, when ePDCCH reception is enabled or configured for a WTRU or UE and the WTRU or UE is configured to receive more than one DL serving cell, the PUCCH resource corresponding to the first DL designation message received on the first ePDCCH is It may be derived by the WTRU or UE as a function of the second DL designation message received on the second DL control channel.

Additionally, in an embodiment, the WTRU or UE may decode the legacy PDCCH on the primary (DL) serving cell while decoding the ePDCCH on the secondary (DL) serving cell. The PUCCH resource used may be determined by the WTRU or UE as a function of the DL designation message received on the primary serving cell. In the case of 2 DL serving cells, PUCCH format 1 derived by channel selection resources can be obtained from the DL designation message of the primary cell. For PUCCH format 3, the WTRU or UE selects PUCCH resources from a set of pre-configured RRC signaling parameters using a signaled resource selector, e.g., the ARI carried in the DL designation message of (e)PDCCH in the secondary serving cell. You can choose.

A WTRU or UE may also decode the ePDCCH on both primary and secondary serving cells. In such an embodiment, the PUCCH resources used may be determined by the WTRU or UE as a function of the first ePDCCH to transmit UL control information such as an A/N corresponding to one or more received DL designations of the ePDCCH. can be used In the case of 2 DL serving cells, PUCCH format 1 derived by channel selection resources can be obtained from the DL designation message of the primary cell.

Embodiments for PUCCH resource allocation by a single set of ePDCCH resources are also described herein. For example, if eCCE and/or eREG units of ePDCCH are defined similarly to legacy PDCCH, the corresponding PUCCH resource is defined as n ⁽¹⁾ _PUCCH,j = n _eCCE + N ^PDCCH _CCE + N ⁽¹⁾ _PUCCH or In the case of a transmission mode that can be derived and supports up to two transport blocks, PUCCH resources (n ⁽¹⁾ _{PUCCH,j + 1} ) are n ⁽¹⁾ _{PUCCH,j + 1} = n _eCCE + N ^PDCCH _CCE + It may be defined or derived as 1 + N ⁽¹⁾ _PUCCH . Here, n _eCCE is the number of first eCCEs used for transmission of the corresponding PDCCH in the ePDCCH region (eg, the lowest eCCE index used to configure the PDCCH), and N ^PDCCH _CCE is the control region for the legacy PDCCH. is the total number of CCEs in , N ⁽¹⁾ _PUCCH can be configured by higher layers. N ^PDCCH _CCEs may be dynamically calculated based on detection of the PCFICH (eg, detection of the number of OFDM symbols) and system bandwidth. N ^PDCCH _CCE may be set to a predefined offset value, for example, the maximum number of CCEs of the maximum system bandwidth, and configured by higher layers to N ⁽¹⁾ _ePUCCH = N ⁽¹⁾ _PUCCH + N ^PDCCH _CCE N ⁽¹⁾ It can be combined with _PUCCH .

In an embodiment, the PUCCH resource may be independent of neCCE so that n ⁽¹⁾ _PUCCH,j = N ⁽¹⁾ _ePUCCH , and N ⁽¹⁾ _ePUCCH may be configured by higher layers. In the case of a transmission mode supporting up to two transport blocks, PUCCH resources (N ⁽¹⁾ _{PUCCH,j + 1} ) may be given by n ⁽¹⁾ _{PUCCH,j + 1} = N ⁽¹⁾ _ePUCCH + 1.

로서 도출될 수 있고, 복수(예를 들면, 최대 2개)의 운송 블록을 지원하는 송신 모드의 경우에, PUCCH 자원 n⁽¹⁾ _PUCCH,j+1은

에 의해 도출될 수 있다. 여기에서, n_MU는 하기의 것 중 적어도 하나로서 결정될 수 있다: UE 특유형 DMRS에 대한 안테나 포트와 연합되는 파라미터; 상위층 시그널링에 의해 구성된 ARI와 유사한 파라미터; 2차 서빙 셀의 (e)PDCCH에서 DL 지정 메시지의 TPC 필드로 운반되는 ARI와 유사한 파라미터(예를 들면, Rel-10에 대한 것처럼) 및/또는 미리 정해진 파라미터.Additionally, if the WTRU or UE is configured for MU-MIMO transmission, the corresponding PUCCH resource is

Can be derived as, and in the case of a transmission mode supporting a plurality (eg, up to two) transport blocks, PUCCH resource n ⁽¹⁾ _{PUCCH,j + 1} is

can be derived by Here, n _MU may be determined as at least one of the following: a parameter associated with an antenna port for UE-specific DMRS; parameters similar to ARI configured by higher layer signaling; An ARI-like parameter (eg, as for Rel-10) and/or a predetermined parameter carried in the TPC field of the DL designation message in (e)PDCCH of the secondary serving cell.

로서 도출될 수 있고, 최대 2개의 운송 블록을 지원하는 송신 모드의 경우에, PUCCH 자원 n⁽¹⁾ _PUCCH,j+1은

로서 도출될 수 있다. 여기에서 n_eCCE는 UE에 대하여 구성된 ePDCCH 집합의 영역에서 대응 PDCCH의 송신을 위해 사용된 제1 eCCE의 수(예를 들면, PDCCH를 구성하기 위해 사용된 최저 eCCE 인덱스)이고,

는 ePDCCH 집합의 PUCCH 자원 오프셋이며, N⁽¹⁾ _PUCCH는 상위층에 의해 구성될 수 있다.

는 동적으로 신호되거나 반정적으로 구성될 수 있다.

는 N⁽¹⁾ _PUCCH와 결합하여 N⁽¹⁾ _ePUCCH = N⁽¹⁾ _PUCCH + N^PDCCH _CCE로 될 수 있고, N⁽¹⁾ _ePUCCH는 동적으로 신호되거나 반정적으로 또는 상위층에 의해 구성될 수 있다. 만일 WTRU 또는 UE가 MU-MIMO 송신으로 구성되면, 대응하는 PUCCH 자원은

로서 도출될 수 있고, 최대 2개의 운송 블록을 지원하는 송신 모드의 경우에, PUCCH 자원 n⁽¹⁾ _PUCCH,j+1은

에 의해 도출될 수 있다. 여기에서, n_MU는 하기의 것 중 적어도 하나로서 결정될 수 있다: UE 특유형 DMRS에 대한 안테나 포트와 연합되는 파라미터; 상위층 시그널링에 의해 구성된 ARI와 유사한 파라미터; 2차 서빙 셀의 (e)PDCCH에서 DL 지정 메시지의 TPC 필드로 운반되는 ARI와 유사한 파라미터(예를 들면, Rel-10에 대한 것처럼) 및/또는 미리 정해진 파라미터.In PUCCH resource allocation by a plurality of ePDCCH resource sets, PUCCH resources for the plurality of ePDCCH resource sets may be defined as follows. If an eCCE or eREG unit of an ePDCCH set is defined similarly to a legacy PDCCH, the corresponding PUCCH resource for the UE is

Can be derived as, and in the case of a transmission mode supporting up to two transport blocks, PUCCH resource n ⁽¹⁾ _{PUCCH,j + 1} is

can be derived as Here, n _eCCE is the number of first eCCEs used for transmission of the corresponding PDCCH in the region of the ePDCCH set configured for the UE (eg, the lowest eCCE index used to configure the PDCCH),

is the PUCCH resource offset of the ePDCCH set, and N ⁽¹⁾ _PUCCHs may be configured by higher layers.

can be dynamically signaled or semi-statically configured.

may be combined with N ⁽¹⁾ _PUCCH , resulting in N ⁽¹⁾ _ePUCCH = N ⁽¹⁾ _PUCCH + N ^PDCCH _CCE , and N ⁽¹⁾ _ePUCCH may be signaled dynamically or configured semi-statically or by higher layers. . If the WTRU or UE is configured for MU-MIMO transmission, the corresponding PUCCH resource is

Can be derived as, and in the case of a transmission mode supporting up to two transport blocks, PUCCH resource n ⁽¹⁾ _{PUCCH,j + 1} is

can be derived by Here, n _MU may be determined as at least one of the following: a parameter associated with an antenna port for UE-specific DMRS; parameters similar to ARI configured by higher layer signaling; An ARI-like parameter (eg, as for Rel-10) and/or a predetermined parameter carried in the TPC field of the DL designation message in (e)PDCCH of the secondary serving cell.

In case of PUCCH format 3, the WTRU or UE selects PUCCH resources from a set of pre-configured RRC signaling parameters using a signaled resource selector, e.g., the ARI carried in the DL designation message of (e)PDCCH via the secondary serving cell can choose

Based on the foregoing, in the case of a single carrier for using an explicitly configured PUCCH resource, an implicitly derived PUCCH resource, or a combination of the two, PUCCH format 3 is a plurality of DL serving cells, For example, it may be used for carrier aggregation with a primary DL serving cell and at least one secondary cell.

A PDSCH transmission mode associated with the ePDCCH may also be provided and/or used as described herein. For example, in the case of PDSCH transmission, several transmission modes supporting various channel/system environments such as closed-loop spatial multiplexing mode, open-loop spatial multiplexing mode, transmission diversity, and/or single-antenna port mode may be used in the system. can The transmission mode may be configured through higher layer signaling, for example, to allow the eNB scheduler to select an appropriate transmission mode for PDSCH transmission. Table 3 shows transmission modes supported in LTE/LTE-A. A transmission mode using antenna ports 7 to 10 for PDSCH demodulation may use ePDCCH. If the WTRU or UE is configured for a specific transmission mode, for example transmission mode 2 using CRS for PDSCH demodulation, the WTRU or UE may monitor the legacy PDCCH for PDSCH reception. If the WTRU or UE is configured to monitor the ePDCCH and the configured transmission mode for the PDSCH is 2 (eg, transmit diversity mode), the WTRU or UE monitors the legacy PDCCH to receive the DCI associated with the PDSCH in a subframe. can do. If the WTRU or UE is configured to monitor ePDCCH and the configured transmission mode for PDSCH is 9, then the WTRU or UE shall monitor ePDCCH to receive DCI of the WTRU or UE-specific search space in the subframe configured for ePDCCH reception. can

Additionally, ePDCCH can be used regardless of the transmission mode configured for PDSCH transmission. For example, the transmission mode or CQI reporting mode configured for the WTRU or UE may be implicitly associated with the ePDCCH transmission type. Depending on the configured transmission mode, the supportable ePDCCH transmission type may be different. For example, if the WTRU or UE is configured with an open loop transmission mode such as transmission diversity (eg TM mode-2) or open loop spatial multiplexing mode (eg TM mode-3), the WTRU or UE may assume that the set of ePDCCH resources configured for the WTRU or UE is used as distributed transmission. The open loop transmission mode for PDSCH can be associated with ePDCCH distributed transmission. The closed loop transmission mode for PDSCH can be associated with ePDCCH localized transmission. Depending on the configured CQI reporting mode, supportable ePDCCH transmission types may be different. For example, if a WTRU or UE is configured for reporting mode using PMI and CQI reporting, the WTRU or UE may assume that the ePDCCH resource set configured for the WTRU or UE is used as a local transmission. If the WTRU or UE is configured for the wideband CQI reporting mode of the PUSCH reporting mode, the WTRU or UE may assume that the ePDCCH resource set configured for the WTRU or UE is for distributed transmission. Otherwise, the WTRU or UE may assume that the set of ePDCCH resources configured for the WTRU or UE is for localized transmission or local and distributed transmission. If the WTRU or UE is configured for CoMP transmission mode, the WTRU or UE may also assume that the ePDCCH resource set configured for the WTRU or UE is specified as localized transmission.

A system and/or method for ePDCCH reception is provided herein. For example, a WTRU or UE may be configured with ePDCCH or legacy PDCCH, and the WTRU or UE behavior to receive ePDCCH may be as follows. A WTRU or UE may receive ePDCCH configuration information in broadcast information. For example, the MIB or SIB contains the ePDCCH procedure so that the WTRU or UE can know the ePDCCH resource before the RACH procedure. To receive broadcast information such as SIB, a WTRU or UE may decode the SI-RNTI of the legacy PDCCH. A WTRU or UE may be configured to receive legacy PDCCH and/or ePDCCH during a RACH procedure. In case of a contention based RACH procedure, the WTRU or UE may receive the PDCCH configuration information in msg2 or msg4 which may be transmitted from the eNB. In case of a non-contention based RACH procedure, the WTRU or UE may receive PDCCH configuration information in msg2 or handover/mobility information that may be transmitted from the eNB. When a WTRU or UE is configured with a particular PDCCH type, the WTRU or UE may blind decode DCI in the configured PDCCH region (eg, legacy PDCCH or ePDCCH). When a WTRU or UE is configured with a specific PDCCH type, the WTRU or UE can blind decode the common search space in the legacy PDCCH region and the WTRU or UE-specific search space in the ePDCCH region.

In an embodiment, a system and/or method for PDCCH fallback transmission is also disclosed. For example, the ePDCCH is further defined on top of the legacy PDCCH and the eNB may configure the legacy PDCCH or ePDCCH in a WTRU or UE specific manner to utilize the PDCCH resources. If the PDCCH resource is configured by higher layer signaling, there may be an obscurity period in which the eNB does not know whether the WTRU or UE is monitoring the legacy PDCCH or the ePDCCH. A WTRU or UE may use at least one of the following to receive PDCCH regardless of PDCCH configuration.

The eNB transmits both legacy PDCCH and ePDCCH in the same subframe during the obscurity period, and can detect from the DTX of the HARQ-ACK which PDCCH resource the WTRU or UE is monitoring. PUCCH resources of legacy PDCCH and ePDCCH may be independently defined.

A common search space is defined in the legacy PDCCH and a fallback transmission mode (eg, DCI format 1A) can be used during the obscurity period. The PDCCH resource configuration may indicate a legacy PDCCH or ePDCCH for a WTRU or UE specific search space. For example, in one embodiment, the fallback PDCCH resource may be defined in the broadcast channel. A common search space is defined in a legacy PDCCH or ePDCCH through a broadcast channel (eg, SIB-x), and the common search space may not change according to a PDCCH configuration.

Additionally, the PDCCH type may be configured by legacy PDCCH or ePDCCH with an activation timer. If the WTRU or UE monitors the legacy PDCCH, the triggering PDCCH based on the legacy PDCCH may be used to notify the WTRU or UE to monitor the ePDCCH from subframe n+x when the triggering PDCCH is received in subframe n, where x can be predefined or configured. If the WTRU or UE monitors the ePDCCH, the triggering ePDCCH based on the ePDCCH may be used to notify the WTRU or UE to monitor the legacy PDCCH from subframe n+x when the triggering ePDCCH is received in subframe n, where x may be predefined or configured.

MAC CEs with activation and/or deactivation commands may be used to configure PDCCH types according to embodiments. For example, the activate and/or deactivate commands can be sent by a timer equal to x, so that if the WTRU or UE receives a MAC CE in subframe n, the commands activate and/or deactivate in subframe n+x. can be, where x can be predefined or configured.

According to an exemplary embodiment, if multiple component carriers are configured, at least one of the following may be used to handle the ambiguous period. For example, a common search space may be defined in the legacy PDCCH of the PCell and cross-carrier scheduling may be activated. In addition, cross-carrier scheduling is activated for common search space and can be used in legacy PDCCH regions. A WTRU or UE specific search space may also be specified in legacy PDCCH and/or ePDCCH (eg, with or without cross-carrier scheduling).

Embodiments for handling or avoiding collisions with other signals are also described herein. The ePDCCH RB may be the same as the RB where the ePDCCH candidate is located. Although the case where there is a collision between the ePDCCH and the PRS is described, the embodiments described herein can be applied to other cases, for example, to other signals including reference signals or broadcast channels in which the ePDCCH resource is different. Although described in terms of handling or avoiding collisions with other signals, the embodiments described herein may be used in other cases, e.g. ePDCCH to/from a given resource element (RE), RB or subframe for some reason. It can be applied to limit or otherwise limit.

In an embodiment, WTRU or UE reception of PRS information may be provided and/or used. For example, a WTRU or UE may receive PRS information for a cell, such as a cell reading ePDCCH or a cell configured for ePDCCH, for reasons other than positioning. A WTRU or UE may receive the information from the eNB via RRC signaling, which may be dedicated or broadcast signaling, for example. A WTRU or UE may receive the information included in the ePDCCH configuration, which may be received in dedicated or broadcast signaling. The given cell on which the WTRU or UE receives this information may be the serving cell of the WTRU or UE, such as, for example, a primary serving cell (Pcell) or a secondary serving cell (Scell). The WTRU or UE may also receive this information about neighboring cells as part of mobility information, or as part of configuration for handover to another serving cell.

In an exemplary embodiment, information that a WTRU or UE may receive for a given cell includes the subframe in which the PRS is transmitted, the PRS configuration index, the PRS period, the PRS offset, the PRS muting period, the PRS muting sequence (e.g., which PRS conditions may be muted in each PRS muting period), and/or an indication of whether the cell transmits a PRS. For a PRS muting sequence that may be included as part of the PRS muting information, if a p-bit field is used to indicate a muting sequence of duration p, the first bit of the field indicates that the PRS muting sequence was received by the WTRU or UE. It may correspond to the first PRS positioning situation starting after the beginning of SFN=0 of the cell to be.

In an embodiment, eNB scheduling may be used or performed. For example, the eNB may schedule and/or transmit the ePDCCH in a way to avoid collision of the ePDCCH RB and PRS RB or to reduce the impact of the collision. In a subframe in which an eNB transmits a PRS in a given cell, the eNB may schedule or not transmit an ePDCCH on any RB in that cell. In a subframe in which an eNB transmits a PRS in a given cell, the eNB may schedule or not transmit an ePDCCH in an RB overlapping the PRS BW of the cell, eg, an RB colliding with the PRS BW of the cell. The eNB may configure the ePDCCH in a given cell in a way that the eNB does not collide with the PRS of the subframe in which the eNB transmits that cell's PRS. This can be applied, for example, when the PRS BW is not the complete DL BW of the cell.

Whether an eNB schedules or transmits the ePDCCH in a given subframe or a given RB may be based on whether or how many ePDCCH DM-RS REs collide with PRS REs. For example, if one or more ePDCCH RBs collide with a PRS RE in a given subframe in which an eNB transmits a PRS, one or more of the following may apply: The eNB may apply an ePDCCH DM-RS RE if in a colliding RB If PRS does not collide with RE, ePDCCH may be transmitted in the colliding RB or in that subframe; The eNB may not transmit the ePDCCH in the colliding RB or in its subframe if at least one ePDCCH DM-RS RE in the colliding RB collides with the PRS RE; The eNB may not transmit the ePDCCH in the colliding RB or in its subframe if a given ePDCCH DM-RS RE collides with the PRS RE in the colliding RB; The eNB may not transmit ePDCCH in the colliding RB or in its subframe if at least a predetermined number of ePDCCH DM-RS REs in the colliding RB collide with PRS REs; An eNB may determine if, due to a collision of an ePDCCH RE and a PRS RE in a colliding RB, a predetermined or at least a predetermined number of antenna ports are unavailable for use in the RB, which may be due to a collision of one or more ePDCCH REs and a PRS RE. , the ePDCCH may not be transmitted in the colliding RB or in that subframe; etc.

An embodiment in which a WTRU or UE receives an ePDCCH, for example for collision handling, is described herein. The WTRU may determine whether to monitor or attempt decoding of an ePDCCH candidate in a given subframe or cell's RB based on one or more PRS parameters or transmission characteristics of that cell. The WTRU or UE may consider the subframe in which the PRS is transmitted. For example, in a subframe in which a PRS is transmitted, the WTRU or UE may monitor or attempt to decode the PDCCH candidate in that subframe and may not monitor or attempt decoding the ePDCCH candidate in that subframe (or may be allowed to monitor or not to try).

In an embodiment, a WTRU or UE may consider the subframe and RB in which the ePDCCH and/or PRS are transmitted. For example, in a subframe in which a PRS is transmitted, the WTRU or UE may not monitor or attempt to decode the ePDCCH candidate in that subframe if the ePDCCH candidate is located on an RB that collides with the PRS RB (or monitor or attempt to decode the ePDCCH candidate). may be permitted not to). In a subframe in which a PRS is transmitted, the WTRU or UE may not (or may be allowed not to) do one or more of the following: if at least one ePDCCH candidate is located in a RB that collides with the PRS RB and monitoring or attempting to decode the ePDCCH candidate in that subframe, if any; If more than a predetermined number of ePDCCH candidates are located in an RB colliding with a PRS RB, monitoring or attempting decoding of the ePDCCH candidates in the subframe; If an ePDCCH candidate (eg, each or all of the candidates) of the subframe is located in an RB colliding with the PRS RB, monitoring or attempting decoding of the ePDCCH candidate in the subframe; monitoring or attempting to decode an ePDCCH candidate located in an RB colliding with a PRS RB; etc. In subframes in which PRSs are transmitted, the WTRU may monitor or attempt (or may be requested to monitor or attempt) decoding one or more of the following: ePDCCH candidates located on RBs that do not collide with PRS RBs in the cell. And / or a predetermined (eg, each or all) when there is no ePDCCH candidate located in an RB colliding with the PRS RB (eg, when there is no overlap between the RB and the PRS BW where the ePDCCH candidate is located) ePDCCH candidates.

Additionally, the WTRU or UE may consider the subframe and RB in which the PRS is transmitted, and may consider whether or how many PRS REs collide with ePDCCH DM-RS REs, for example. In the subframe in which the PRS is transmitted, the WTRU or UE may monitor or attempt to decode the ePDCCH candidate located in the RB colliding with the PRS RB if no ePDCCH DM-RS RE in the colliding RB collides with the PRS RE; (or may be required to monitor or attempt); If at least one ePDCCH DM-RS RE in the colliding RB collides with the PRS RE, decoding of the ePDCCH candidate located in the RB colliding with the PRS RB may not be monitored or attempted (or may be allowed not to monitor or attempt) have); If a predetermined ePDCCH DM-RS RE collides with a PRS RE in a colliding RB, decoding of an ePDCCH candidate located in an RB colliding with a PRS RB may not be monitored or attempted (or may be allowed to monitor or not attempt ); If at least a predetermined number of ePDCCH DM-RS REs in colliding RBs collide with PRS REs, decoding of ePDCCH candidates located in RBs colliding with PRS RBs may not be monitored or attempted (or may be allowed not to monitor or attempt) can); If a predetermined or at least a predetermined number of antenna ports in a colliding RB become unavailable for use in that RB, which may result from a collision of one or more ePDCCH REs with the PRS RE, the ePDCCH candidate located in the RB colliding with the PRS RB may not monitor or attempt to decode (or may be allowed not to monitor or attempt); etc.

In a given cell, in a subframe in which PRS is transmitted, the WTRU or UE determines the value of the PRS v _shift value, which can be defined as the physical layer cell ID, v _shift = N ^cell _ID mod6, where N ^cell _ID is the physical layer cell identity. , or monitoring or attempting (or being required to monitor or attempting) or not monitoring or attempting (or ePDCCH candidates (allowed not to be monitored or attempted) may be determined. One or more of these parameters may be used by the WTRU to locate a PRS RE that the WTRU or UE may use to determine which ePDCCH DM-RS RE collides with the PRS RE.

In a subframe in which a PRS is transmitted in a given cell, a WTRU or UE may monitor or attempt (or be required to monitor or attempt) or not monitor or attempt decoding based at least on the number of antenna ports configured for ePDCCH in that cell. ePDCCH candidates that do not (or are allowed not to be monitored or attempted) may be determined. If an antenna port is restricted in a subframe, the WTRU may use the port after the restriction instead of the configured port in that subframe for the decision. For example, antenna ports {7, 8, 9, 10} can be used in regular subframes and antenna ports {7, 8} or {9, 10} can be used in certain subframes.

In other embodiments, a search space fallback may be implemented or used. For example, in the case of a WTRU configured for ePDCCH, the PDCCH may include a common search space. In a given subframe, such as the subframe in which the PRS is transmitted, the PDCCH may contain a WTRU or UE specific search space for the WTRU or UE configured for the ePDCCH. If a WTRU or UE configured for ePDCCH in a subframe does not monitor or attempt (or is permitted not to monitor or attempt) decoding of an ePDCCH candidate, e.g., according to one of the solutions described herein, the WTRU or UE may may monitor or attempt (or may be required to monitor or attempt) decoding of the common search space and/or the WTRU or UE-specific search space in the region.

For example, a WTRU or UE configured for ePDCCH may fall back to monitor or attempt to decode PDCCH candidates specified within the WTRU or UE specific search space of the PDCCH region. Fallback may be provided or used in a subframe in which a PRS is transmitted in a cell and/or PRS information (e.g., one or more of the information items described herein), PRS transmission parameters, physical layer cell ID, cell or subframe ( For example, it may be based on at least one of the CP length in normal or extended type), the number of antenna ports configured for ePDCCH transmission, antenna port restrictions, and the like.

A given subframe may be configured as a fallback subframe. The eNB may provide such a configuration to the WTRU or UE. According to an exemplary embodiment, such a configuration may be received by the WTRU or UE from the eNB via broadcast signaling or dedicated signaling such as RRC signaling.

For subframes configured as fallback subframes, a WTRU or UE configured for ePDCCH may not monitor or attempt (or may be allowed not to monitor or attempt) decoding of the ePDCCH candidate. For a subframe configured as a fallback subframe, for a given WTRU or UE, such as a WTRU or UE configured for ePDCCH, the WTRU or UE's WTRU or UE-specific search space may be defined in the PDCCH region. In subframes such as these subframes, the WTRU or UE may monitor or attempt to decode PDCCH candidates, such as common search space PDCCH candidates and/or WTRU or UE specific search space PDCCH candidates, in the PDCCH region (or monitor or may be requested to try). For subframes not configured as fallback subframes, a given WTRU or UE, such as a WTRU or UE configured for ePDCCH, may monitor or attempt (or may be required to monitor or attempt decoding of the ePDCCH candidate in the PDSCH region). there is). The fallback subframe may be composed of at least one of a period, an offset, the number of consecutively configured subframes (eg, the number of consecutive DL subframes), and/or other parameters.

In addition, the configuration of the ePDCCH subframe or the ePDCCH monitoring subframe may be the same as that of the fallback subframe, and in this case, the ePDCCH subframe or the ePDCCH monitoring subframe may be processed in a manner opposite to that of the fallback subframe. For example, the WTRU or UE and/or eNB may process subframes not configured as ePDCCH subframes or ePDCCH monitoring subframes in the manner described herein for subframes configured as fallback subframes. The WTRU or UE and/or eNB may process subframes configured as ePDCCH subframes or ePDCCH monitoring subframes in the manner described herein for subframes not configured as fallback subframes.

Embodiments dealing with PRS REs are described herein. In a subframe in which a PRS is transmitted, for an ePDCCH candidate located in an RB that the WTRU or UE is trying to decode, the WTRU or UE may send a RE containing data (e.g., CRS or DM-RS or CSI-RS). For non-nested REs), it can be assumed that the ePDCCH is not transmitted in an RE that collides with the PRS RE. The WTRU or UE may assume that the ePDCCH RE is accordingly ambient rate matched to and/or punctured at such RE.

A WTRU or UE may have and/or obtain knowledge about PRS parameters and/or transmission characteristics from information provided to the WTRU or UE, and may use such information for collision handling. For example, a WTRU or UE may obtain knowledge from the E-SMLC (eg, via LPP signaling) or from an eNB (eg, via RRC signaling). The parameters may include any one or more of those described herein as well as others.

From the above and/or other parameters, the WTRU or UE may determine the subframe and/or RB of the subframe in which the PRS is transmitted in a given cell. A WTRU or UE may or may not consider PRS muting when determining in which subframe of a cell PRS is transmitted.

When determining if a DM-RS RE, e.g. ePDCCH DM-RS RE collides with a PRS RE in an RB of a given cell, the WTRU or UE determines the CP length of the subframe or cell, the number of antenna ports configured for ePDCCH transmission, One or more of the cell's physical cell ID and a PRS v _shift value that can be derived from the cell's physical cell ID, for example v _shift = N ^cell _ID mod6, can be used.

In addition, location or antenna port mapping may be used for DM-RS REs according to example embodiments, for example for collision handling. The eNB may change the arrangement of the DM-RS RE in the RB where the ePDCCH candidate is located in the subframe of the cell in which the PRS is transmitted. In a subframe in which the eNB transmits the PRS in a given cell, the eNB may change the arrangement of the DM-RS RE such as the ePDCCH DM-RS RE to avoid collision with the PRS RE. The eNB may change the arrangement of the DM-RS RE such as the ePDCCH DM-RS RE if at least one DM-RS RE collides with the PRS RE in a different way. The eNB may change the placement of DM-RS REs such as ePDCCH DM-RS REs that collide with PRS REs in other ways.

A given DM-RS RE whose placement has been moved is one or more (or all) DM-RS REs that collide with the PRS REs in other ways, and if the DM-RS REs have not been moved, the DM-RS REs that collide with the PRS REs and One or more (or all) DM-RS REs with the same carrier frequency, and/or one or more (or all) DM-RS REs on carrier frequencies adjacent to the DM-RS REs colliding with the PRS REs if the DM-RS REs have not moved. DM-RS REs (eg, if a DM-RS RE with frequency X collides with a PRS RE, a DM-RS RE on a frequency adjacent to X may be moved).

In a subframe in which a PRS is transmitted, an interpretation of an antenna port by an eNB may be modified in relation to a DM-RS such as an ePDCCH DM-RS. The interpretation is at least one or more of the cell's physical cell ID, the cell's PRS v _shift , CP length (eg, for a cell, subframe or normal subframe), and/or the number of antenna ports configured for ePDCCH transmission. can be a function

A change in placement may occur in frequency, for example an increase or decrease in frequency. Placement changes may or may not include a change of symbols. The change in placement is at least one or more of the cell's physical cell ID, the cell's PRS v _shift , CP length (eg, for a cell, subframe or normal subframe), and/or the number of antenna ports configured for ePDCCH transmission. can be a function

In a cell in which the eNB transmits the PRS, the eNB may change the arrangement of the DM-RS RE such as the ePDCCH DM-RS RE in a given subframe to avoid or reduce collision with the PRS RE in the subframe in which the eNB transmits the PRS. can The predetermined subframe may include a subframe in which the eNB transmits a PRS and/or a subframe in which the eNB does not transmit a PRS. For example, the predetermined subframe may include all subframes. The eNB can change the placement as described above. In this cell (e.g., the cell in which the eNB transmits the PRS), the interpretation of the antenna ports by the eNB in relation to the DM-RS, such as the ePDCCH DM-RS, is a desirable modification in the subframe in which the eNB transmits the PRS. It can be modified in a given subframe to align with . The predetermined subframe may include a subframe in which the eNB transmits a PRS and/or a subframe in which the eNB does not transmit a PRS. For example, the predetermined subframe may include all subframes. .

In a cell where the eNB may or may not transmit a PRS, the eNB may change the placement of the DM-RS RE such as the ePDCCH DM-RS RE based on where the PRS is placed if the cell needs to transmit the PRS. An eNB may change its placement as described herein. In this cell (e.g., a cell in which the eNB may or may not transmit PRS), interpretation of the antenna ports by the eNB in relation to DM-RS, such as ePDCCH DM-RS, is desirable if the cell needs to transmit PRS. It can be modified in that subframe to align with being modified.

The eNB may move the DM-RS RE or modify the antenna port interpretation in one or more of the methods described for the ePDCCH DM-RS RE in a given subframe. The eNB may, for example, move the DM-RS RE or modify the antenna port interpretation for the PDSCH licensed by the ePDCCH of the subframe in the same or similar manner.

In subframes in which PRSs are transmitted, the WTRU or UE may use a modified DM-RS pattern (eg, this may be different from the DM-RS pattern used for ePDCCHs in subframes in which PRSs are not transmitted) to transmit the ePDCCH The candidate's decoding can be monitored or attempted. In this subframe (eg, the subframe in which the PRS is transmitted), the interpretation of antenna ports by the WTRU or UE may be modified with respect to DM-RS, such as ePDCCH DM-RS. The interpretation is at least one or more of the cell's physical cell ID, the cell's PRS v _shift , CP length (eg, for a cell, subframe or normal subframe), and/or the number of antenna ports configured for ePDCCH transmission. can be a function

In one or more subframes (e.g., which may include all subframes) of cells transmitting PRS, the WTRU or UE may use a modified DM-RS pattern (e.g., this is the ePDCCH of cells not transmitting PRS). Decoding of the ePDCCH candidate may be monitored or attempted using a DM-RS pattern that may be different from the DM-RS pattern used for . In this subframe (e.g., the subframe of one or more (which may include all) of the cell transmitting the PRS), the number of antenna ports by the WTRU or UE in connection with a DM-RS such as the ePDCCH DM-RS Interpretation may be modified. The interpretation may be a function of at least one of the cell's physical cell ID, the cell's PRS v _shift , and/or the number of antenna ports configured for ePDCCH transmission.

The modified DM-RS pattern and / or antenna port interpretation is the location of the PRS RB, the location of the PRS RE, the cell's physical layer cell ID, the cell's PRS v _shift , CP length (eg, for a cell, subframe or normal subframe), and/or the number of antenna ports configured for ePDCCH transmission.

According to an embodiment, a WTRU or UE may use a modified DM-RS pattern or antenna port interpretation to decode a PDSCH, such as a PDSCH granted by an ePDCCH that may use a modified DM-RS pattern or antenna interpretation. . For example, a WTRU or UE may decode a PDSCH granted by an ePDCCH of a subframe in which the ePDCCH uses a modified DM-RS pattern, such as the same or similar pattern used for the ePDCCH DM-RS. -RS pattern can be used. As another example, a WTRU or UE may decode a PDSCH granted by an ePDCCH of a subframe in which the ePDCCH uses a modified antenna port interpretation, such as an interpretation identical to or similar to that used for the ePDCCH DM-RS. interpretation is available.

Additionally, embodiments for collision handling, for example, are described in terms of antenna port restrictions for DM-RS REs. For example, the eNB may grant antenna port restrictions in an RB in which an ePDCCH candidate is located in a subframe of a cell in which a PRS is transmitted. In a subframe in which an eNB transmits a PRS in a given cell, the eNB may restrict the use of certain antenna ports for ePDCCH and/or PDSCH. Such constraints are dependent on at least one of the cell's physical layer cell ID, the cell's PRS v _shift , CP length (eg, for a cell, subframe or normal subframe), and/or the number of antenna ports configured for ePDCCH transmission. can be based As an example, if antenna ports 7, 8, 9, and 10 are configured for ePDCCH transmission, restrictions to limit to ports 7 and 8 or ports 9 and 10 may be imposed in the subframe in which the PRS is transmitted, such The restriction may be based on at least one of the cell's physical layer cell ID, PRS v _shift , and/or CP length (eg, for a cell, subframe or normal subframe).

In the subframe in which the PRS is transmitted, the WTRU or UE may monitor or attempt decoding of the ePDCCH candidate using a limited set of antenna ports. A WTRU or UE may use a limited set of antenna ports, such as the same or similar limited set of antenna ports used for ePDCCH, for PDSCH licensed by the ePDCCH of a subframe in which ePDCCH uses a limited set of antenna ports. When using a limited set of antenna ports, the limited set may replace the configured set of antenna ports or another set of antenna ports, for example with any solution or embodiment described herein.

Other ePDCCH configurations may be implemented for certain subframes such as PRS subframes (eg for collision handling). In such an embodiment, for a cell, there may be a different configuration for ePDCCH for use in subframes in which PRSs are transmitted than for ePDCCHs for use in subframes in which PRSs are not transmitted. In the subframe in which the PRS is transmitted, the WTRU or UE may monitor or attempt to decode the ePDCCH candidate according to the configuration for that subframe. A WTRU or UE may receive the ePDCCH configuration for the subframe in which the PRS is transmitted from the eNB via dedicated or broadcast signaling, which may be RRC signaling, for example. A WTRU or UE may receive one or more ePDCCH configurations, and may receive instructions regarding which configurations are used and when, for example from an eNB. For example, the command may indicate in which subframe (eg, a subframe in which a PRS is transmitted or a subframe in which a PRS is not transmitted) or under which circumstances a given configuration is used.

In subframes in which PRSs are transmitted, PRSs may also be overridden (eg, for collision handling). For example, a RE such as an ePDCCH RE may override a PRS RE. Overriding the first signal with respect to the second signal inhibits transmission of the second signal, while transmission of the first signal is enabled. For example, RE1 may override RE2, where RE1 or signals within RE1 may be transmitted and RE2 or signals within RE2 may not be transmitted.

In a subframe in which the PRS is transmitted, the RE may override the PRS RE (eg, when colliding with the PRS RE). For example, such an override may occur when one or more of the following occurs or becomes true: when the RE is an ePDCCH DM-RS RE such as any ePDCCH DM-RS RE; when the RE is a predetermined ePDCCH DM-RS RE, for example an ePDCCH DM-RS RE corresponding to a predetermined antenna; when the RE is an ePDCCH DM-RS RE (eg, any ePDCCH DM-RS RE) in the ePDCCH common search space; when the RE is an RE in the ePDCCH common search space equal to any RE in the ePDCCH common search space; etc.

When a RE such as ePDCCH RE or ePDCCH DM-RS RE overrides the PRS RE, collisions between REs and PRS REs can be eliminated or avoided (e.g., if a signal within the PRS RE or PRS RE is not transmitted). because it doesn't). If a conflict between the RE and the PRS RE is removed or avoided, for example by override, the WTRU may determine that there is no conflict between the RE and the PRS RE. Based on this determination, the WTRU may make various decisions, such as whether to monitor or attempt decoding of the ePDCCH candidate, ie the ePDCCH candidate located in the RB or RE of the subframe in which the PRS is transmitted in the cell.

Blind decoding (eg optimization thereof) may be performed (eg for collision handling). For example, based on the configured ePDCCH resource, the WTRU or UE may perform multiple blind decoding, which may be referred to as full set blind decoding. As an example, if some of the ePDCCH candidates are located on RBs in which a PRS collides with a PRS RB of a subframe transmitted in a cell, the WTRU or UE may monitor or attempt to decode the subset of the configured RBs in which the ePDCCH candidate is located. can In such a scenario, the WTRU or UE may do one or more of the following: use full set blind decoding on a subset of RBs (eg, to recover full decoding for subframes); and/or use a blind decoding set in a subset of RBs equal to or larger than the set for the RB as part of the overall configuration and a subset of RBs equal to or smaller than the overall set of the overall configuration. For example, if the full set of RBs corresponds to N blind decodings and the partial set corresponds to M out of the N, then when attempting to decode the partial set (or only the partial set), the WTRU or UE W blind decodings may be used, where W may be equal to N or M≤W≤N.

Additionally, in an embodiment (eg, for collision handling), the eNB has knowledge of WTRU or UE positioning capabilities and/or which WTRUs or UEs know about PRS transmissions and/or PRS parameters. have or can be acquired. For example, an eNB may send information regarding WTRU or UE positioning capabilities and/or which WTRUs or UEs in one or more cells have PRS transmissions and/or knowledge of PRS parameters to an E-SMLC or other network entity. can be received from The eNB may request and/or receive this and/or other information via, for example, an LPPa interface or protocol. For a given or given WTRU or UE (or multiple WTRUs or UEs), this information may include one or more of the following: whether the WTRU or UE has the capability to support OTDOA; whether PRS information was provided to the WTRU or UE (eg, by E-SMLC or other network entity as part of positioning assistance data); For which cell or cells the PRS information was provided (e.g., cells under the control of the eNB, which may be the serving cell or cells of the WTRU or UE) and for which cell or cells the information was provided to the WTRU or UE. ; and/or whether the PRS information was successfully received by the WTRU or UE, etc. PRS information includes one or more of PRS transmission subframes, BW, RB, RE, muting information, and/or any other information related to PRS (eg, PRS information as described herein or parameters from which the listed information is determined). can include

The E-SMLC and/or other network entity determines whether PRS information has been successfully received by the WTRU or UE, and in response to successful reception of said information provided by the E-SMLC or other network entity, an arrival notification from the WTRU or UE ( ACK) or other indication. If there is no ACK or other indication from the WTRU or UE in response to the E-SMLC or other network entity providing the PRS information, the E-SMLC or other network entity's knowledge of the WTRU or UE awareness of the PRS information is not reliable. .

A WTRU or UE may also handle PRS information from one or more sources (eg, for collision handling). For example, a WTRU or UE may receive PRS information for a cell from at least one source, such as an E-SMLC, an eNB controlling cell transmission of PRS, another cell, or another network entity. A WTRU or UE may treat the PRS information it receives as described herein.

Knowledge of the cell's PRS transmission information by the WTRU or UE could become stale or unreliable if, for example, the information was received from an E-SMLC or other network entity other than the eNB that controls or has knowledge of the PRS transmission. can For example, even if the eNB notifies the E-SMLC or other network entity when the PRS transmission parameters for one or more cells have changed, if the WTRU or UE sends the PRS information about the cell and PRS information change, e.g. at a rather late time. If received, the PRS information known to the WTRU or UE may be inaccurate. This information may become inaccurate until the eNB notifies the E-SMLC or other network entity of the change and/or until the E-SMLC or other network entity notifies the WTRU or UE.

The WTRU or UE may use (or only use) the PRS information it receives from the eNB, for example, to determine how to handle the ePDCCH in the cell transmitting the PRS or within the cell's PRS subframe. The eNB may be the eNB responsible for PRS transmission in the cell, or another eNB that provides configuration for that cell to the WTRU or UE (eg, as part of information provided in signaling related to handover). A WTRU or UE may not use PRS information received from another source, such as an E-SMLC or other network entity, to determine how to handle ePDCCHs within the cell transmitting the PRS or within a PRS subframe of the cell, for example. Yes (or may not be allowed to use it). This may be provided (or advantageous) when the eNB does not know which WTRU or UE obtained the PRS information from another source such as the E-SMLC or other network entity. The WTRU or UE behavior may be unknown to or unpredictable by the eNB if the WTRU or UE must use information received from other sources. The eNB may send different PRS information to the WTRU or UE than that sent to the WTRU or UE by the E-SMLC or other network entity to achieve the desired action.

A WTRU or UE may use the PRS information received from the E-SMLC or other network entity to determine, for example, how to handle the ePDCCH in the transmitting cell or a PRS subframe of the cell. If the WTRU or UE receives PRS information for a given cell from multiple sources, the WTRU or UE expects the information from multiple sources to be the same, otherwise the behavior may be unspecified. A WTRU or UE may consider the PRS information of a given cell received from the eNB to override previously received PRS information from the source (eg, any source), for example for ePDCCH handling purposes. A WTRU or UE may consider a given cell's PRS information received from any source to override PRS information previously received from the source (eg, any source), e.g., for ePDCCH handling purposes.

Also described are embodiments that handle ePHICH collisions with PRS (eg, for collision handling). For a subframe in which PRS is transmitted, one or more of the following may apply: ePHICH may override PRS if ePHICH collides with PRS; If the DM-RS RE of ePHICH conflicts with the PRS RE, the DM-RS RE of ePHICH may override the PRS RE; and/or if the ePHICH RE collides with the PRS RE, the ePHICH RE may be rate matched around the PRS RE. The WTRU or UE may take this into account when monitoring or attempting to decode the ePHICH.

One or more embodiments described herein for handling ePDCCH or ePDCCH and PRS may be applied to handle ePHICH or ePHICH and PRS. For example, a WTRU configured for at least one ePDCCH or ePHICH may fall back to monitor or attempt decoding of the PHICH, and/or a subframe in which the fallback is configured, ePDCCH or ePDCCH monitoring or ePHICH or ePHICH monitoring is not configured. It may not monitor or attempt to decode the ePHICH in subframes, subframes in which PRSs are transmitted, or subframes where collisions or potential collisions with PRSs within such subframes warrant such behavior in accordance with one or more embodiments described herein. there is.

Quasi-collocated antenna ports may also be provided and/or used depending on the embodiment. Demodulation of a given downlink channel, e.g., PDSCH in a given transmission mode, allows the WTRU or UE to channel from a reference signal, such as a WTRU or UE specific reference signal (e.g., received via antenna ports 7-14). It may be necessary to estimate As part of such a procedure, the WTRU or UE may perform fine-grained time and/or frequency synchronization to the reference signal as well as estimation of certain properties related to the large-scale characteristics of the propagation channel.

In one embodiment, such a procedure is facilitated under the assumption that other regularly measurable reference signals, such as cell-specific reference signals, share the same timing (and some other properties) as the WTRU or UE-specific reference signals. It can be. Such an assumption may hold if the signals are physically transmitted from the same set of antennas. On the other hand, for embodiments with geographically dispersed antennas, the above assumption will not be valid when the WTRU or UE-specific reference signal (and associated downlink channel) is transmitted from a different point than the cell-specific reference signal. can Thus, a WTRU or UE may be informed via a reference signal (eg, CSI-RS) that shares the same timing and/or other characteristics as the reference signal used for demodulation. Corresponding antenna ports (e.g., two antenna ports) may then be “quasi-coexisting,” so that the WTRU or UE may have large-scale attributes of signals received from the first antenna port to signals received from the other antenna port. It can be inferred from The "large-scale property" may include one or more of the following: delay spread; Doppler spread; frequency shift; average received power; reception timing; etc. As described herein, the ePDCCH may be demodulated using reference signals transmitted on antenna ports such as antenna ports 7 to 10. To exploit the potential capacity benefits of the ePDCCH as well as the region partitioning gains, the ePDCCH may also be transmitted from the cell's transmission point. To transmit an ePDCCH from a transmission point of a cell, a user equipment (UE) needs to use and/or know one or more reference signals, such as CSI-RS, which can be quasi-coexistent with the antenna port used for demodulation of the ePDCCH. . Unfortunately, knowledge and use of such a reference signal that can be quasi-coexistent with the antenna port used for demodulation of the ePDCCH can be difficult as the downlink control information that can potentially be signaled tends to become available after decoding of the ePDCCH. can

Thus, a system and/or method for providing a demodulation reference timing indication is described herein. For example, a single demodulation reference timing may be provided and/or used. In such an embodiment (eg, the first embodiment), the WTRU or UE has at least one quasi-coexistence antenna port predefined antenna port (eg, port 0 through which the cell-specific reference signal is transmitted). 3) and/or at least one antenna port configured by higher layers (e.g., at least one of ports 15 to 23 of one configuration for the CSI-RS reference signal). can The network may transmit the ePDCCH to the WTRU or UE via the same transmission point corresponding to the predefined or preconfigured quasi-coexistence antenna port. The network may also transmit the ePDCCH through another transmission point if the network knows that the large scale properties of the reference signals transmitted from this point are sufficiently similar so as not to affect the demodulation performance. For example, in one embodiment, if antenna port 0 (CRS) is defined as a quasi-coexistence antenna port and the CRS is transmitted from a node (including a high-power node and a low-power node), the network determines that the transmitted from the low-power node When the network knows that the reception timing of the reference signal is sufficiently close to the reception timing of the CRS, the ePDCCH may be transmitted from a predetermined low-power node.

To implement such an embodiment, a WTRU or UE may estimate at least one attribute of at least one reference signal, such as a CSI-RS, known by the network to be transmitted from a given transmission point. The attributes being measured may include at least one of the following: receive timing, average received power, frequency shift, Doppler spread, delay spread, and the like.

At least one of the above attributes may relate to the same attribute for another predefined or configured reference signal. For example, the WTRU or UE may estimate the difference in reception timing between the reference signal concerned and the cell specific reference signal (CRS). As another example, the WTRU or UE may estimate the ratio (in dB) between the average received power of the reference signal concerned and the CRS.

In one embodiment, to calculate the estimate, the WTRU or UE may perform averaging over two or more antenna ports on which the reference signals concerned are transmitted. The WTRU or UE may also perform averaging over multiple subframes and multiple resource blocks (eg, in the frequency domain). A new measurement type may also be defined for each of the foregoing attributes.

The WTRU or UE may report the measurement result for at least one attribute to the network using an RRC message (eg, measurement report) or lower layer signaling (eg, MAC control element or physical layer signaling). Using these results, the network assumes, identifies, or determines which antenna ports (or reference signals) are quasi-coexistent with the antenna ports utilized for demodulation, whether transmission from a given point is feasible, based on what the WTRU or UE has identified or determined. may be determined by doing so or considering such a decision. For example, if the difference in timing due to the CRS assumed, identified or determined by the WTRU or UE to be quasi-coexistent is too large, the network may transmit using the same transmission point as used for the CRS (e.g. , taking into account any loss or split of gains).

Additionally, in an embodiment, the WTRU or UE may periodically trigger transmission of measurement results. Additionally, the WTRU or UE may trigger transmission of the result when at least one of the following events occurs. A WTRU or UE may trigger a transmission when a difference in an attribute between reference signals becomes higher or lower than a threshold. For example, a WTRU or UE may trigger transmission of a report when a received timing difference between a CRS and a given configured CSI-RS becomes higher than a threshold. The WTRU or UE may also trigger a transmission when the absolute value of an attribute of the reference signal goes above or below a threshold. For example, the WTRU or UE may trigger transmission of a report if the measured delay spread rises above a threshold. Such events and associated parameters or thresholds may be configured as part of a measurement reporting configuration (eg reportConfig).

The network also measures uplink transmissions from WTRUs or UEs, such as SRS, PUCCH, PUSCH or PRACH, etc. at other reception points that coincide with the transmission points potentially used for downlink transmissions to determine whether some large-scale attributes are similar (e.g. For example, when the received timings are similar) can be estimated.

A plurality of demodulation reference timings may be provided and/or used. In such embodiments (eg, the second embodiment), to receive ePDCCH and/or PDSCH based on WTRU or UE specific reference signals (eg, antenna ports 7-14), see below At least one of the signals may be used to indicate demodulation reference timing for the WTRU or UE, i.e. CSI-RS, CRS, PRS, etc.

If the WTRU or UE is provided or notified about the demodulation reference timing along with the reference signal, the WTRU or UE demodulation process including TFT timing and channel estimation filter coefficients may follow the reference signal. For example, if there are two CSI-RS configured for a WTRU or UE, such as CSI-RS ₁ and CSI-RS ₂ , and the WTRU or UE reports CSI for both CSI-RS configurations, the TFT for PDSCH demodulation Timing and fine time and/or frequency synchronization may follow one of the two CSI-RS configurations according to the demodulation reference timing indication.

Alternatively, if the WTRU or UE is notified of demodulation reference timing along with a reference signal, the PDSCH demodulation procedure may be different depending on the type of reference signal based on one or more of the following.

If CSI is used for reference timing, the TFT timing and channel estimation filter coefficients for CSI-RS can be used for PDSCH demodulation. For example, a WTRU or UE may assume, identify, or determine that the PDSCH and/or WTRU or UE-specific demodulated RS (eg, antenna ports 7-14) are transmitted from the same quasi-coexisting antenna port. So, if a WTRU or UE is configured to monitor the ePDCCH (eg, for each PRB set), the WTRU or UE may send the first set of antenna ports (eg, 15-22) the CSI-RS information It may be assumed, identified or determined that the information is related to or corresponds to that information, and/or the mapping to the PDSCH and other antenna ports (eg, 7-14 or other ports) is a Doppler shift, Doppler spread, as described above. , it can be identified that it becomes quasi-coexistent with respect to parameters such as average delay, delay spread, etc.

If CRS is used for reference timing, FFT timing and channel estimation filter coefficients of CRS can be used for PDSCH demodulation. Alternatively, the time and/or frequency offset of the CRS may be provided for PDSCH demodulation. If the WTRU or UE is notified of the offset, the WTRU or UE may apply the offset from the CRS. In an exemplary embodiment, at least one of the following offsets may be provided: FFT timing offset (ΔFFT), time offset (ΔT), frequency offset (ΔF), and the like.

If PRS is used for reference timing, WTRU or UE behavior similar to CSI-RS or CRS may be applied in such an embodiment.

In an embodiment, the demodulation reference timing may be communicated to the WTRU or UE in an implicit or explicit manner. Also, a single demodulation reference for a given time window (eg, subframe or radio frame) may be applied or multiple demodulation references may be used.

An implicit demodulation reference timing indication may be provided and/or used. In such an embodiment (eg, the first solution), the demodulation reference timing may be associated with the ePDCCH and/or PDCCH resource and implicitly informed to the WTRU or UE. Since the DCI must be received to demodulate the PDSCH, the demodulation timing reference can be inferred from the location of the ePDCCH and/or PDCCH resource, when the WTRU or UE can receive the DCI. At least one of the following methods may be used to implement ePDCCH and/or PDCCH resource-based indication.

In one embodiment, the WTRU or UE-specific search space may be divided into two or more subsets, and each subset may be associated with a specific demodulation timing reference. For example, within a WTRU or UE-specific search space, the total blind decoding attempts (2N _blind ) can be divided into two subsets (subset ₁ and subset ₂ ), each subset being exclusive N _blinds . decoding attempts, where each subset may be combined with a different demodulation timing reference. For example, subset ₁ may be combined with CRS-RS ₁ and subset ₂ may be combined with CSI-RS ₂ . So, in one embodiment, if a WTRU or UE receives a DCI for a PDSCH in subset ₁ , the WTRU or UE can assume, identify or determine that the PDSCH is transmitted on the same transmission point with CSI-RS ₁ . there is.

Additionally, as described herein, for an ePDCCH WTRU or UE specific search space, a search space subset may be combined with a demodulation timing reference. Therefore, when the WTRU or UE performs blind decoding on the ePDCCH, the WTRU or UE assumes that subset ₁ and subset ₂ are transmitted from the same reference point with CSI-RS ₁ and CSI-RS ₂ respectively, identifying or can decide In another embodiment, as described herein, if a WTRU or UE receives DCI on an ePDCCH, the WTRU or UE may assume, identify, or determine that the corresponding PDSCH is transmitted from the same transmission point along with the ePDCCH. Also, for an ePDCCH common search space (eg, as described herein), a WTRU or UE may assume, identify, or determine that the ePDCCH is transmitted from the same transmission point along with the CRS.

So, in an embodiment, if the WTRU or UE is configured to monitor the ePDCCH (eg, for each PRB set), the WTRU or UE may use the CSI-RS to determine mapping information and/or antenna port quasi-coexistence. A parameter set indicated by a higher layer parameter such as may be used (eg, ePDCCH).

According to another embodiment (eg the second solution), the demodulation antenna port may be combined with a demodulation timing reference. If antenna ports 7-10 are available for ePDCCH and/or PDSCH demodulation, multiple quasi-coexistence port pairs may be predefined. For example, a WTRU or UE may assume, identify, or determine that antenna ports {7, 8} and {9, 10} are quasi-coexisting, where quasi-coexisting pairs {7, 8} and {9, 10} may be combined with CSI-RS ₁ and CSI-RS ₂ , respectively. For such an embodiment, the WTRU or UE may also assume, identify, or determine that the demodulation timing reference for antenna port-7 is the same as antenna port-8. Alternatively, the scrambling IDs (n _SCIDs ) may also be combined with demodulation timing references, assuming that a plurality of n _SCIDs are used. If n _SCID =0 and n _SCID =1 are used, the WTRU or UE assumes, identifies or determines that n _SCID =0 is associated with CSI-RS ₁ and n _SCID =1 is associated with CSI-RS ₂ , for example. can According to another alternative example, n _SCIDs may be combined with antenna ports. For example, n _SCID = 0 may be used for antenna ports {7, 8} and n _SCID = 1 may be used for antenna ports {9.10}. So, the WTRU or UE will use n _SCID =0 when the WTRU or UE demodulates signals based on antenna port {7, 8} and when the WTRU or UE demodulates signals based on antenna port {9, 10} It can be assumed, identified or determined that n _SCID = 1 is used. The antenna ports for n _SCID mappings may consist of at least one of the following: The antenna ports for n _SCID mappings may be predefined, and in such an embodiment, the quasi-coexisting antenna ports will have the same n _SCIDs . can; Antenna ports for n _SCID mapping can be configured by broadcast channels or higher layer signaling; etc.

The scrambling sequence may be initialized by the following equation.

In the above c _init , N ^X _ID is a higher layer configurable value or a predefined value as a physical cell ID.

In another embodiment (eg, the third solution), downlink resources may be combined with demodulation timing references. In such an embodiment, depending on the downlink resource location for ePDCCH and/or PDSCH, the WTRU or UE may infer demodulation reference timing. A downlink location may include at least one of the following: A PRB configured to use a subset of downlink subframes and/or a specific demodulation reference timing. Optionally, the reference time can be used for demodulation of antenna ports 7 to 14. Alternatively, CRS can be used as a reference timing.

In another embodiment (eg, the fourth solution), the demodulation reference timing may be defined by the time relationship with CSI-RS and CSI feedback. WTRU or UE behavior in such an embodiment may be defined by at least one of the following. The WTRU or UE may assume, identify or determine that the PDSCH is transmitted from the transmission point with CSI-RS _k if the last CSI-RS received by the WTRU or UE is CSI-RS _k . In such an embodiment, the subframe offset may be further defined such that the WTRU or UE may assume, identify or determine that the demodulation reference timing changes after a plurality of offset subframes.

Additionally, the WTRU or UE may assume, identify, or determine that the PDSCH is transmitted from the transmission point with CSI-RS _k if the last CSI feedback reported by the WTRU or UE is based on CSI-RS _k , where In , the final CSI feedback may be at least one of the following: aperiodic CSI reporting; periodic CSI report with PMI/CQI (where the demodulation reference timing can be kept invariant if the last CSI report type was RI); Periodic CSI reporting with PMI/CQI/RI; an offset subframe to which demodulation reference timing may be applied to change after a plurality of offset subframes; etc.

An implicit indication of PDSCH demodulation information may also be provided and/or used as described herein. For example, as described herein, a method or procedure may be used to determine PDSCH demodulation information that a WTRU or UE may use when decoding a PDSCH, for example, in a subframe. PDSCH demodulation information may include one or more of the following. For example, the PDSCH demodulation information may include a reference signal (eg, or antenna port) estimated as a quasi-coexistence type for a reference signal (eg, or antenna port) that can be used for PDSCH demodulation. (eg, including indexes for non-zero power CSI-RS resources). PDSCH demodulation information is at least one that can be used to determine the location of a resource element (RE) on which a PDSCH is transmitted, or on which a PDSCH is not transmitted (e.g., for rate matching purposes), such as one or more of the following: It may also include parameters of: at least one parameter (eg, number of CRS ports, CRS frequency shift) indicating a location of a CRS port on which a PDSCH is not transmitted; MBSFN configuration; At least one parameter indicating a location of a zero-power CSI-RS in which a PDSCH is not transmitted, such as a configuration of a zero-power CSI-RS; Indication of PDSCH start symbol; at least one parameter indicating a location of a non-zero power CSI-RS in which a PDSCH is not transmitted; at least one parameter indicating a location of a resource element that can be used for an interference measurement resource; etc. Additionally, the PDSCH demodulation information may also include a scrambling identity that may be used to determine a demodulation reference signal.

In one exemplary embodiment (eg, exemplary method), a WTRU or UE may use PDSCH demodulation information to demodulate an ePDCCH containing designation (eg, control information) for the PDSCH. It may be determined based on the identity (eg, CRS or CSI-RS, etc.) of the reference signal estimated as a quasi-coexistence type for the reference signal. In such an embodiment (eg, method), the network may use the same transmission point for the ePDCCH and the PDSCH that may be signaled by the same ePDCCH. In addition, since some PDSCH demodulation information is coupled (eg, sometimes closely coupled) to an engineered transmission point, such information can be implicitly derived from a reference signal assumed to be quasi-coexistence.

For example, if the WTRU or UE determines that a non-zero power CSI-RS resource is coexisting in a reference signal that can be used for the ePDCCH, the WTRU or UE may use the same non-zero power CSI-RS resource to demodulate the PDSCH. It can be estimated that it corresponds to the reference signal coexisting with the reference signal to be. In addition, the index of the non-zero power CSI-RS resource may indicate a set of parameters (eg, possibly along with another indication of downlink control information) that determines PDSCH demodulation information that may be configured by higher layers. there is.

In another embodiment (eg, exemplary method), the WTRU or UE may transmit PDSCH demodulation information to the ePDCCH including downlink control information applicable to the PDSCH, e.g., a search space, or the ePDCCH is decoded. It may be determined based on attributes (eg, other attributes) of the ePDCCH set, aggregation level, whether the corresponding ePDCCH set is distributed or local, and the like.

In an exemplary embodiment, use of one or more of the foregoing embodiments or methods may depend on at least one of the following: an indication from higher layers that PDSCH demodulation information may be obtained using the method; Indication from downlink control information applicable to this PDSCH (e.g., this method may be applied if either a new field or a specific subset of values of an existing field is received, and for a different value of this field , the WTRU or UE may obtain PDSCH demodulation information based on the value of the field); For example, the configured DCI format, the configured transmission mode (e.g., applicable to TM10), the configured behavior for determining the ePDCCH coexistence reference signal (e.g., this method is Applicable if obtained based on the set of ePDCCHs to be decoded), RRC configuration based on whether the non-zero power CSI-RS resources configured for each ePDCCH set are different for the purpose of determining quasi-coexistence; etc.

An explicit demodulation reference timing indication may be provided and/or used. In such an embodiment (eg, the first solution), the demodulation reference timing may be indicated or included in the DCI of the PDSCH. For example, an indication bit may be explicitly placed in the DCI. So, the WTRU or UE can be informed which demodulation reference timing is used for the corresponding PDSCH demodulation. Alternatively, the demodulation reference timing may be informed to the WTRU or UE via higher layer signaling (eg RRC, MAC control element, etc.).

In another embodiment (eg, the second solution), the demodulation reference timing may be indicated via a specific ePDCCH and/or PDCCH such that the demodulation reference timing varies from subframe to subframe in a WTRU or UE specific manner. In such an embodiment, ePDCCH and/or PDCCH may use at least one of the following: ePDCCH and/or PDCCH may trigger one of demodulation reference timing and the triggered demodulation reference timing may be predefined or in higher layer signaling. may be valid for a window of time configurable by; ePDCCH and/or PDCCH may trigger one of the demodulation reference timings and the triggered demodulation reference timing may be effective as long as no other demodulation reference timing is triggered; ePDCCH and/or PDCCH may be used for activation/deactivation to indicate demodulation reference timing.

WTRU or UE blind decoding of multiple demodulation reference timings may also be provided and/or used according to exemplary embodiments. For example, without demodulation reference timing information, the WTRU or UE may blindly attempt multiple demodulation reference timings at the receiver. For such an embodiment, the WTRU or UE may demodulate the ePDCCH and/or PDCCH with each possible demodulation reference timing candidate. For example, if two CSI-RSs are configured for a WTRU or UE, and the WTRU or UE reports CSI for both CSI-RS configurations, the WTRU or UE may use the ePDCCH and/or PDCCH by both CSI-RS configurations. can be demodulated.

Although the terms WTRU or UE are used herein, it should be understood that the use of such terms can be used interchangeably, so there is no difference. Additionally, for the enhanced physical downlink control channel described herein, ePDCCH, EPDCCH and/or ePDCCH may be used interchangeably.

Although the terms legacy PDCCH or PDCCH are used herein to indicate Rel-8/9/10 PDCCH resources, it should be understood that the usage of such terms can be used interchangeably, so there is no difference. Additionally, PDCCH and DCI may be used interchangeably to mean downlink control information transmitted from an eNB to a WTRU or UE.

Additionally, while features and elements have been described so far in particular combinations, those skilled in the art will understand that each feature or element may be used alone or in any combination with other features and elements. In addition, the methods described herein may be implemented as a computer program, software or firmware incorporated in a computer readable medium executed by a computer or processor. Examples of computer readable media include electronic signals (transmitted over wired or wireless connections) and computer readable storage media. Non-limiting examples of computer-readable storage media include read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and Optical media such as CD-ROM disks and digital versatile disks (DVDs). A processor, in conjunction with software, may be used to implement a radio frequency transceiver used in a WTRU, UE, terminal, base station, RNC, or any host computer.

106, 107, 109: Core network 110: Internet
112 other network 118 processor
120: transceiver 124: speaker/microphone
126: keypad 128: display/touchpad
130: non-removable memory 132: removable memory
134: power supply 136: GPS chipset
138: Peripherals 140a, 140b, 140c: Node-B
160a, 160b, 160c: eNode-B 164: Serving Gateway
166: PDN gateway 180a, 180b, 180c: base station
182: ASN Gateway 188: Gateway

Claims (20)

A method for using an enhanced physical downlink control channel (ePDCCH), implemented by a wireless transmit and receive unit (WTRU), comprising:
Receiving a configuration, the configuration comprising: (i) indicating a plurality of ePDCCH resource sets; (ii) a demodulation reference signal (DM-RS) for each of the plurality of ePDCCH resource sets; ) indicating a scrambling sequence initialization parameter, and (iii) indicating demodulation timing reference information for processing each of the plurality of ePDCCH resource sets, wherein the demodulation timing reference information comprises: Also for demodulating PDSCH transmission -;
Monitoring at least one search space associated with each of the plurality of ePDCCH resource sets, wherein the at least one search space is initialized with a DM-RS scrambling sequence initialization parameter for a corresponding ePDCCH resource set. - the WTRU monitoring a search space, excluding time and frequency resources occupied by the DM-RS of the RS sequence;
Receiving at least one ePDCCH transmission on at least one of the plurality of ePDCCH resource sets.
Including, method. According to claim 1,
The demodulation timing reference information includes information to be used to determine a demodulation timing reference, and the demodulation timing reference information includes a first channel state information reference signal (CSI-RS) associated with a first ePDCCH, and And a second CSI-RS associated with a second ePDCCH. According to claim 1,
wherein the demodulation timing reference information includes an indication of a pair of antenna ports, the pair of antenna ports being quasi-collocated for ePDCCH processing. According to claim 3,
wherein the pair of antenna ports are each associated with a common channel state information reference signal (CSI-RS). According to claim 3,
wherein the quasi-coexisting pair of antenna ports have a common Doppler shift, Doppler spread, average delay and delay spread. According to claim 1,
wherein each set of ePDCCH resources is associated with a different network transmission port. According to claim 1,
wherein the at least one search space is a WTRU-specific search space. According to claim 1,
Wherein the configuration indicating a plurality of ePDCCH resource sets indicates a number of PRB-pairs for each of the plurality of ePDCCH resource sets. According to claim 1,
Wherein the configuration is received through any of broadcast signaling and higher layer signaling. According to claim 9,
The higher layer signaling includes any of radio resource control (RRC) signaling and medium access control (MAC) control element (CE) signaling. In a wireless transmit and receive unit (WTRU),
contains a processor;
the processor,
Receive a configuration, the configuration comprising: (i) indicating a plurality of enhanced physical downlink control channel (ePDCCH) resource sets; and (ii) a demodulation reference signal (DM-RS) for each of the plurality of ePDCCH resource sets. ) indicate a scrambling sequence initialization parameter; (iii) indicate demodulation timing reference information for processing each of the plurality of ePDCCH resource sets, the demodulation timing reference information also for demodulating a PDSCH transmission;
Monitoring at least one search space associated with each of the plurality of ePDCCH resource sets—the at least one search space of a DM-RS sequence initialized with a DM-RS scrambling sequence initialization parameter for a corresponding ePDCCH resource set; Excluding the time and frequency resources occupied by RS—
To receive at least one ePDCCH transmission on at least one of the plurality of ePDCCH resource sets.
A wireless transmit/receive unit (WTRU), which is configured. According to claim 11,
The demodulation timing reference information includes information to be used to determine a demodulation timing reference, and the demodulation timing reference information includes a first channel state information reference signal (CSI-RS) associated with a first ePDCCH and a second channel state information reference signal (CSI-RS) associated with a second ePDCCH. A wireless transmit/receive unit (WTRU) comprising a CSI-RS. According to claim 11,
wherein the demodulation timing reference information includes an indication of a pair of antenna ports, the pair of antenna ports being quasi-coexisting for ePDCCH processing. According to claim 13,
wherein the pair of antenna ports are each associated with a common channel state information reference signal (CSI-RS). According to claim 13,
wherein the quasi-coexisting pair of antenna ports have a common Doppler shift, Doppler spread, average delay and delay spread. According to claim 11,
wherein each set of ePDCCH resources is associated with a different network transmit port. According to claim 11,
wherein the at least one search space is a WTRU-specific search space. According to claim 11,
wherein the configuration indicating a plurality of ePDCCH resource sets indicates a number of PRB-pairs for each of the plurality of ePDCCH resource sets. According to claim 11,
wherein the configuration is received via any of broadcast signaling and higher layer signaling. According to claim 19,
wherein the higher layer signaling includes any of radio resource control (RRC) signaling and medium access control (MAC) control element (CE) signaling.

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